refactor: move brother_node development artifact to dev/test-nodes subdirectory

Development Artifact Cleanup:
✅ BROTHER_NODE REORGANIZATION: Moved development test node to appropriate location
- dev/test-nodes/brother_node/: Moved from root directory for better organization
- Contains development configuration, test logs, and test chain data
- No impact on production systems - purely development/testing artifact

✅ DEVELOPMENT ARTIFACTS IDENTIFIED:
- Chain ID: aitbc-brother-chain (test/development chain)
- Ports: 8010 (P2P) and 8011 (RPC) - different from production
- Environment: .env file with test configuration
- Logs: rpc.log and node.log from development testing session (March 15, 2026)

✅ ROOT DIRECTORY CLEANUP: Removed development clutter from production directory
- brother_node/ moved to dev/test-nodes/brother_node/
- Root directory now contains only production-ready components
- Development artifacts properly organized in dev/ subdirectory

DIRECTORY STRUCTURE IMPROVEMENT:
📁 dev/test-nodes/: Development and testing node configurations
🏗️ Root Directory: Clean production structure with only essential components
🧪 Development Isolation: Test environments separated from production

BENEFITS:
✅ Clean Production Directory: No development artifacts in root
✅ Better Organization: Development nodes grouped in dev/ subdirectory
✅ Clear Separation: Production vs development environments clearly distinguished
✅ Maintainability: Easier to identify and manage development components

RESULT: Successfully moved brother_node development artifact to dev/test-nodes/ subdirectory, cleaning up the root directory while preserving development testing environment for future use.

dev/env/node_modules/@openzeppelin/contracts/account/extensions/draft-AccountERC7579.sol

@@ -0,0 +1,405 @@
+// SPDX-License-Identifier: MIT
+// OpenZeppelin Contracts (last updated v5.4.0) (account/extensions/draft-AccountERC7579.sol)
+
+pragma solidity ^0.8.26;
+
+import {PackedUserOperation} from "../../interfaces/draft-IERC4337.sol";
+import {IERC1271} from "../../interfaces/IERC1271.sol";
+import {IERC7579Module, IERC7579Validator, IERC7579Execution, IERC7579AccountConfig, IERC7579ModuleConfig, MODULE_TYPE_VALIDATOR, MODULE_TYPE_EXECUTOR, MODULE_TYPE_FALLBACK} from "../../interfaces/draft-IERC7579.sol";
+import {ERC7579Utils, Mode, CallType, ExecType} from "../../account/utils/draft-ERC7579Utils.sol";
+import {EnumerableSet} from "../../utils/structs/EnumerableSet.sol";
+import {Bytes} from "../../utils/Bytes.sol";
+import {Packing} from "../../utils/Packing.sol";
+import {Address} from "../../utils/Address.sol";
+import {Calldata} from "../../utils/Calldata.sol";
+import {Account} from "../Account.sol";
+
+/**
+ * @dev Extension of {Account} that implements support for ERC-7579 modules.
+ *
+ * To comply with the ERC-1271 support requirement, this contract defers signature validation to
+ * installed validator modules by calling {IERC7579Validator-isValidSignatureWithSender}.
+ *
+ * This contract does not implement validation logic for user operations since this functionality
+ * is often delegated to self-contained validation modules. Developers must install a validator module
+ * upon initialization (or any other mechanism to enable execution from the account):
+ *
+ * ```solidity
+ * contract MyAccountERC7579 is AccountERC7579, Initializable {
+ *   function initializeAccount(address validator, bytes calldata validatorData) public initializer {
+ *     _installModule(MODULE_TYPE_VALIDATOR, validator, validatorData);
+ *   }
+ * }
+ * ```
+ *
+ * [NOTE]
+ * ====
+ * * Hook support is not included. See {AccountERC7579Hooked} for a version that hooks to execution.
+ * * Validator selection, when verifying either ERC-1271 signature or ERC-4337 UserOperation is implemented in
+ *   internal virtual functions {_extractUserOpValidator} and {_extractSignatureValidator}. Both are implemented
+ *   following common practices. However, this part is not standardized in ERC-7579 (or in any follow-up ERC). Some
+ *   accounts may want to override these internal functions.
+ * * When combined with {ERC7739}, resolution ordering of {isValidSignature} may have an impact ({ERC7739} does not
+ *   call super). Manual resolution might be necessary.
+ * * Static calls (using callType `0xfe`) are currently NOT supported.
+ * ====
+ *
+ * WARNING: Removing all validator modules will render the account inoperable, as no user operations can be validated thereafter.
+ */
+abstract contract AccountERC7579 is Account, IERC1271, IERC7579Execution, IERC7579AccountConfig, IERC7579ModuleConfig {
+    using Bytes for *;
+    using ERC7579Utils for *;
+    using EnumerableSet for *;
+    using Packing for bytes32;
+
+    EnumerableSet.AddressSet private _validators;
+    EnumerableSet.AddressSet private _executors;
+    mapping(bytes4 selector => address) private _fallbacks;
+
+    /// @dev The account's {fallback} was called with a selector that doesn't have an installed handler.
+    error ERC7579MissingFallbackHandler(bytes4 selector);
+
+    /// @dev Modifier that checks if the caller is an installed module of the given type.
+    modifier onlyModule(uint256 moduleTypeId, bytes calldata additionalContext) {
+        _checkModule(moduleTypeId, msg.sender, additionalContext);
+        _;
+    }
+
+    /// @dev See {_fallback}.
+    fallback(bytes calldata) external payable virtual returns (bytes memory) {
+        return _fallback();
+    }
+
+    /// @inheritdoc IERC7579AccountConfig
+    function accountId() public view virtual returns (string memory) {
+        // vendorname.accountname.semver
+        return "@openzeppelin/community-contracts.AccountERC7579.v0.0.0";
+    }
+
+    /**
+     * @inheritdoc IERC7579AccountConfig
+     *
+     * @dev Supported call types:
+     * * Single (`0x00`): A single transaction execution.
+     * * Batch (`0x01`): A batch of transactions execution.
+     * * Delegate (`0xff`): A delegate call execution.
+     *
+     * Supported exec types:
+     * * Default (`0x00`): Default execution type (revert on failure).
+     * * Try (`0x01`): Try execution type (emits ERC7579TryExecuteFail on failure).
+     */
+    function supportsExecutionMode(bytes32 encodedMode) public view virtual returns (bool) {
+        (CallType callType, ExecType execType, , ) = Mode.wrap(encodedMode).decodeMode();
+        return
+            (callType == ERC7579Utils.CALLTYPE_SINGLE ||
+                callType == ERC7579Utils.CALLTYPE_BATCH ||
+                callType == ERC7579Utils.CALLTYPE_DELEGATECALL) &&
+            (execType == ERC7579Utils.EXECTYPE_DEFAULT || execType == ERC7579Utils.EXECTYPE_TRY);
+    }
+
+    /**
+     * @inheritdoc IERC7579AccountConfig
+     *
+     * @dev Supported module types:
+     *
+     * * Validator: A module used during the validation phase to determine if a transaction is valid and
+     * should be executed on the account.
+     * * Executor: A module that can execute transactions on behalf of the smart account via a callback.
+     * * Fallback Handler: A module that can extend the fallback functionality of a smart account.
+     */
+    function supportsModule(uint256 moduleTypeId) public view virtual returns (bool) {
+        return
+            moduleTypeId == MODULE_TYPE_VALIDATOR ||
+            moduleTypeId == MODULE_TYPE_EXECUTOR ||
+            moduleTypeId == MODULE_TYPE_FALLBACK;
+    }
+
+    /// @inheritdoc IERC7579ModuleConfig
+    function installModule(
+        uint256 moduleTypeId,
+        address module,
+        bytes calldata initData
+    ) public virtual onlyEntryPointOrSelf {
+        _installModule(moduleTypeId, module, initData);
+    }
+
+    /// @inheritdoc IERC7579ModuleConfig
+    function uninstallModule(
+        uint256 moduleTypeId,
+        address module,
+        bytes calldata deInitData
+    ) public virtual onlyEntryPointOrSelf {
+        _uninstallModule(moduleTypeId, module, deInitData);
+    }
+
+    /// @inheritdoc IERC7579ModuleConfig
+    function isModuleInstalled(
+        uint256 moduleTypeId,
+        address module,
+        bytes calldata additionalContext
+    ) public view virtual returns (bool) {
+        if (moduleTypeId == MODULE_TYPE_VALIDATOR) return _validators.contains(module);
+        if (moduleTypeId == MODULE_TYPE_EXECUTOR) return _executors.contains(module);
+        if (moduleTypeId == MODULE_TYPE_FALLBACK) return _fallbacks[bytes4(additionalContext[0:4])] == module;
+        return false;
+    }
+
+    /// @inheritdoc IERC7579Execution
+    function execute(bytes32 mode, bytes calldata executionCalldata) public payable virtual onlyEntryPointOrSelf {
+        _execute(Mode.wrap(mode), executionCalldata);
+    }
+
+    /// @inheritdoc IERC7579Execution
+    function executeFromExecutor(
+        bytes32 mode,
+        bytes calldata executionCalldata
+    )
+        public
+        payable
+        virtual
+        onlyModule(MODULE_TYPE_EXECUTOR, Calldata.emptyBytes())
+        returns (bytes[] memory returnData)
+    {
+        return _execute(Mode.wrap(mode), executionCalldata);
+    }
+
+    /**
+     * @dev Implement ERC-1271 through IERC7579Validator modules. If module based validation fails, fallback to
+     * "native" validation by the abstract signer.
+     *
+     * NOTE: when combined with {ERC7739}, resolution ordering may have an impact ({ERC7739} does not call super).
+     * Manual resolution might be necessary.
+     */
+    function isValidSignature(bytes32 hash, bytes calldata signature) public view virtual returns (bytes4) {
+        // check signature length is enough for extraction
+        if (signature.length >= 20) {
+            (address module, bytes calldata innerSignature) = _extractSignatureValidator(signature);
+            // if module is not installed, skip
+            if (isModuleInstalled(MODULE_TYPE_VALIDATOR, module, Calldata.emptyBytes())) {
+                // try validation, skip any revert
+                try IERC7579Validator(module).isValidSignatureWithSender(msg.sender, hash, innerSignature) returns (
+                    bytes4 magic
+                ) {
+                    return magic;
+                } catch {}
+            }
+        }
+        return bytes4(0xffffffff);
+    }
+
+    /**
+     * @dev Validates a user operation with {_signableUserOpHash} and returns the validation data
+     * if the module specified by the first 20 bytes of the nonce key is installed. Falls back to
+     * {Account-_validateUserOp} otherwise.
+     *
+     * See {_extractUserOpValidator} for the module extraction logic.
+     */
+    function _validateUserOp(
+        PackedUserOperation calldata userOp,
+        bytes32 userOpHash
+    ) internal virtual override returns (uint256) {
+        address module = _extractUserOpValidator(userOp);
+        return
+            isModuleInstalled(MODULE_TYPE_VALIDATOR, module, Calldata.emptyBytes())
+                ? IERC7579Validator(module).validateUserOp(userOp, _signableUserOpHash(userOp, userOpHash))
+                : super._validateUserOp(userOp, userOpHash);
+    }
+
+    /**
+     * @dev ERC-7579 execution logic. See {supportsExecutionMode} for supported modes.
+     *
+     * Reverts if the call type is not supported.
+     */
+    function _execute(
+        Mode mode,
+        bytes calldata executionCalldata
+    ) internal virtual returns (bytes[] memory returnData) {
+        (CallType callType, ExecType execType, , ) = mode.decodeMode();
+        if (callType == ERC7579Utils.CALLTYPE_SINGLE) return executionCalldata.execSingle(execType);
+        if (callType == ERC7579Utils.CALLTYPE_BATCH) return executionCalldata.execBatch(execType);
+        if (callType == ERC7579Utils.CALLTYPE_DELEGATECALL) return executionCalldata.execDelegateCall(execType);
+        revert ERC7579Utils.ERC7579UnsupportedCallType(callType);
+    }
+
+    /**
+     * @dev Installs a module of the given type with the given initialization data.
+     *
+     * For the fallback module type, the `initData` is expected to be the (packed) concatenation of a 4-byte
+     * selector and the rest of the data to be sent to the handler when calling {IERC7579Module-onInstall}.
+     *
+     * Requirements:
+     *
+     * * Module type must be supported. See {supportsModule}. Reverts with {ERC7579Utils-ERC7579UnsupportedModuleType}.
+     * * Module must be of the given type. Reverts with {ERC7579Utils-ERC7579MismatchedModuleTypeId}.
+     * * Module must not be already installed. Reverts with {ERC7579Utils-ERC7579AlreadyInstalledModule}.
+     *
+     * Emits a {IERC7579ModuleConfig-ModuleInstalled} event.
+     */
+    function _installModule(uint256 moduleTypeId, address module, bytes memory initData) internal virtual {
+        require(supportsModule(moduleTypeId), ERC7579Utils.ERC7579UnsupportedModuleType(moduleTypeId));
+        require(
+            IERC7579Module(module).isModuleType(moduleTypeId),
+            ERC7579Utils.ERC7579MismatchedModuleTypeId(moduleTypeId, module)
+        );
+
+        if (moduleTypeId == MODULE_TYPE_VALIDATOR) {
+            require(_validators.add(module), ERC7579Utils.ERC7579AlreadyInstalledModule(moduleTypeId, module));
+        } else if (moduleTypeId == MODULE_TYPE_EXECUTOR) {
+            require(_executors.add(module), ERC7579Utils.ERC7579AlreadyInstalledModule(moduleTypeId, module));
+        } else if (moduleTypeId == MODULE_TYPE_FALLBACK) {
+            bytes4 selector;
+            (selector, initData) = _decodeFallbackData(initData);
+            require(
+                _fallbacks[selector] == address(0),
+                ERC7579Utils.ERC7579AlreadyInstalledModule(moduleTypeId, module)
+            );
+            _fallbacks[selector] = module;
+        }
+
+        IERC7579Module(module).onInstall(initData);
+        emit ModuleInstalled(moduleTypeId, module);
+    }
+
+    /**
+     * @dev Uninstalls a module of the given type with the given de-initialization data.
+     *
+     * For the fallback module type, the `deInitData` is expected to be the (packed) concatenation of a 4-byte
+     * selector and the rest of the data to be sent to the handler when calling {IERC7579Module-onUninstall}.
+     *
+     * Requirements:
+     *
+     * * Module must be already installed. Reverts with {ERC7579Utils-ERC7579UninstalledModule} otherwise.
+     */
+    function _uninstallModule(uint256 moduleTypeId, address module, bytes memory deInitData) internal virtual {
+        require(supportsModule(moduleTypeId), ERC7579Utils.ERC7579UnsupportedModuleType(moduleTypeId));
+
+        if (moduleTypeId == MODULE_TYPE_VALIDATOR) {
+            require(_validators.remove(module), ERC7579Utils.ERC7579UninstalledModule(moduleTypeId, module));
+        } else if (moduleTypeId == MODULE_TYPE_EXECUTOR) {
+            require(_executors.remove(module), ERC7579Utils.ERC7579UninstalledModule(moduleTypeId, module));
+        } else if (moduleTypeId == MODULE_TYPE_FALLBACK) {
+            bytes4 selector;
+            (selector, deInitData) = _decodeFallbackData(deInitData);
+            require(
+                _fallbackHandler(selector) == module && module != address(0),
+                ERC7579Utils.ERC7579UninstalledModule(moduleTypeId, module)
+            );
+            delete _fallbacks[selector];
+        }
+
+        IERC7579Module(module).onUninstall(deInitData);
+        emit ModuleUninstalled(moduleTypeId, module);
+    }
+
+    /**
+     * @dev Fallback function that delegates the call to the installed handler for the given selector.
+     *
+     * Reverts with {ERC7579MissingFallbackHandler} if the handler is not installed.
+     *
+     * Calls the handler with the original `msg.sender` appended at the end of the calldata following
+     * the ERC-2771 format.
+     */
+    function _fallback() internal virtual returns (bytes memory) {
+        address handler = _fallbackHandler(msg.sig);
+        require(handler != address(0), ERC7579MissingFallbackHandler(msg.sig));
+
+        // From https://eips.ethereum.org/EIPS/eip-7579#fallback[ERC-7579 specifications]:
+        // - MUST utilize ERC-2771 to add the original msg.sender to the calldata sent to the fallback handler
+        // - MUST use call to invoke the fallback handler
+        (bool success, bytes memory returndata) = handler.call{value: msg.value}(
+            abi.encodePacked(msg.data, msg.sender)
+        );
+
+        if (success) return returndata;
+
+        assembly ("memory-safe") {
+            revert(add(returndata, 0x20), mload(returndata))
+        }
+    }
+
+    /// @dev Returns the fallback handler for the given selector. Returns `address(0)` if not installed.
+    function _fallbackHandler(bytes4 selector) internal view virtual returns (address) {
+        return _fallbacks[selector];
+    }
+
+    /// @dev Checks if the module is installed. Reverts if the module is not installed.
+    function _checkModule(
+        uint256 moduleTypeId,
+        address module,
+        bytes calldata additionalContext
+    ) internal view virtual {
+        require(
+            isModuleInstalled(moduleTypeId, module, additionalContext),
+            ERC7579Utils.ERC7579UninstalledModule(moduleTypeId, module)
+        );
+    }
+
+    /**
+     * @dev Extracts the nonce validator from the user operation.
+     *
+     * To construct a nonce key, set nonce as follows:
+     *
+     * ```
+     * <module address (20 bytes)> | <key (4 bytes)> | <nonce (8 bytes)>
+     * ```
+     * NOTE: The default behavior of this function replicates the behavior of
+     * https://github.com/rhinestonewtf/safe7579/blob/bb29e8b1a66658790c4169e72608e27d220f79be/src/Safe7579.sol#L266[Safe adapter],
+     * https://github.com/etherspot/etherspot-prime-contracts/blob/cfcdb48c4172cea0d66038324c0bae3288aa8caa/src/modular-etherspot-wallet/wallet/ModularEtherspotWallet.sol#L227[Etherspot's Prime Account], and
+     * https://github.com/erc7579/erc7579-implementation/blob/16138d1afd4e9711f6c1425133538837bd7787b5/src/MSAAdvanced.sol#L247[ERC7579 reference implementation].
+     *
+     * This is not standardized in ERC-7579 (or in any follow-up ERC). Some accounts may want to override these internal functions.
+     *
+     * For example, https://github.com/bcnmy/nexus/blob/54f4e19baaff96081a8843672977caf712ef19f4/contracts/lib/NonceLib.sol#L17[Biconomy's Nexus]
+     * uses a similar yet incompatible approach (the validator address is also part of the nonce, but not at the same location)
+     */
+    function _extractUserOpValidator(PackedUserOperation calldata userOp) internal pure virtual returns (address) {
+        return address(bytes32(userOp.nonce).extract_32_20(0));
+    }
+
+    /**
+     * @dev Extracts the signature validator from the signature.
+     *
+     * To construct a signature, set the first 20 bytes as the module address and the remaining bytes as the
+     * signature data:
+     *
+     * ```
+     * <module address (20 bytes)> | <signature data>
+     * ```
+     *
+     * NOTE: The default behavior of this function replicates the behavior of
+     * https://github.com/rhinestonewtf/safe7579/blob/bb29e8b1a66658790c4169e72608e27d220f79be/src/Safe7579.sol#L350[Safe adapter],
+     * https://github.com/bcnmy/nexus/blob/54f4e19baaff96081a8843672977caf712ef19f4/contracts/Nexus.sol#L239[Biconomy's Nexus],
+     * https://github.com/etherspot/etherspot-prime-contracts/blob/cfcdb48c4172cea0d66038324c0bae3288aa8caa/src/modular-etherspot-wallet/wallet/ModularEtherspotWallet.sol#L252[Etherspot's Prime Account], and
+     * https://github.com/erc7579/erc7579-implementation/blob/16138d1afd4e9711f6c1425133538837bd7787b5/src/MSAAdvanced.sol#L296[ERC7579 reference implementation].
+     *
+     * This is not standardized in ERC-7579 (or in any follow-up ERC). Some accounts may want to override these internal functions.
+     */
+    function _extractSignatureValidator(
+        bytes calldata signature
+    ) internal pure virtual returns (address module, bytes calldata innerSignature) {
+        return (address(bytes20(signature[0:20])), signature[20:]);
+    }
+
+    /**
+     * @dev Extract the function selector from initData/deInitData for MODULE_TYPE_FALLBACK
+     *
+     * NOTE: If we had calldata here, we could use calldata slice which are cheaper to manipulate and don't require
+     * actual copy. However, this would require `_installModule` to get a calldata bytes object instead of a memory
+     * bytes object. This would prevent calling `_installModule` from a contract constructor and would force the use
+     * of external initializers. That may change in the future, as most accounts will probably be deployed as
+     * clones/proxy/ERC-7702 delegates and therefore rely on initializers anyway.
+     */
+    function _decodeFallbackData(
+        bytes memory data
+    ) internal pure virtual returns (bytes4 selector, bytes memory remaining) {
+        return (bytes4(data), data.slice(4));
+    }
+
+    /// @dev By default, only use the modules for validation of userOp and signature. Disable raw signatures.
+    function _rawSignatureValidation(
+        bytes32 /*hash*/,
+        bytes calldata /*signature*/
+    ) internal view virtual override returns (bool) {
+        return false;
+    }
+}

dev/env/node_modules/@openzeppelin/contracts/account/extensions/draft-AccountERC7579Hooked.sol

@@ -0,0 +1,107 @@
+// SPDX-License-Identifier: MIT
+// OpenZeppelin Contracts (last updated v5.4.0) (account/extensions/draft-AccountERC7579Hooked.sol)
+
+pragma solidity ^0.8.26;
+
+import {IERC7579Hook, MODULE_TYPE_HOOK} from "../../interfaces/draft-IERC7579.sol";
+import {ERC7579Utils, Mode} from "../../account/utils/draft-ERC7579Utils.sol";
+import {AccountERC7579} from "./draft-AccountERC7579.sol";
+
+/**
+ * @dev Extension of {AccountERC7579} with support for a single hook module (type 4).
+ *
+ * If installed, this extension will call the hook module's {IERC7579Hook-preCheck} before executing any operation
+ * with {_execute} (including {execute} and {executeFromExecutor} by default) and {IERC7579Hook-postCheck} thereafter.
+ *
+ * NOTE: Hook modules break the check-effect-interaction pattern. In particular, the {IERC7579Hook-preCheck} hook can
+ * lead to potentially dangerous reentrancy. Using the `withHook()` modifier is safe if no effect is performed
+ * before the preHook or after the postHook. That is the case on all functions here, but it may not be the case if
+ * functions that have this modifier are overridden. Developers should be extremely careful when implementing hook
+ * modules or further overriding functions that involve hooks.
+ */
+abstract contract AccountERC7579Hooked is AccountERC7579 {
+    address private _hook;
+
+    /// @dev A hook module is already present. This contract only supports one hook module.
+    error ERC7579HookModuleAlreadyPresent(address hook);
+
+    /**
+     * @dev Calls {IERC7579Hook-preCheck} before executing the modified function and {IERC7579Hook-postCheck}
+     * thereafter.
+     */
+    modifier withHook() {
+        address hook_ = hook();
+        bytes memory hookData;
+
+        // slither-disable-next-line reentrancy-no-eth
+        if (hook_ != address(0)) hookData = IERC7579Hook(hook_).preCheck(msg.sender, msg.value, msg.data);
+        _;
+        if (hook_ != address(0)) IERC7579Hook(hook_).postCheck(hookData);
+    }
+
+    /// @inheritdoc AccountERC7579
+    function accountId() public view virtual override returns (string memory) {
+        // vendorname.accountname.semver
+        return "@openzeppelin/community-contracts.AccountERC7579Hooked.v0.0.0";
+    }
+
+    /// @dev Returns the hook module address if installed, or `address(0)` otherwise.
+    function hook() public view virtual returns (address) {
+        return _hook;
+    }
+
+    /// @dev Supports hook modules. See {AccountERC7579-supportsModule}
+    function supportsModule(uint256 moduleTypeId) public view virtual override returns (bool) {
+        return moduleTypeId == MODULE_TYPE_HOOK || super.supportsModule(moduleTypeId);
+    }
+
+    /// @inheritdoc AccountERC7579
+    function isModuleInstalled(
+        uint256 moduleTypeId,
+        address module,
+        bytes calldata data
+    ) public view virtual override returns (bool) {
+        return
+            (moduleTypeId == MODULE_TYPE_HOOK && module == hook()) ||
+            super.isModuleInstalled(moduleTypeId, module, data);
+    }
+
+    /// @dev Installs a module with support for hook modules. See {AccountERC7579-_installModule}
+    function _installModule(
+        uint256 moduleTypeId,
+        address module,
+        bytes memory initData
+    ) internal virtual override withHook {
+        if (moduleTypeId == MODULE_TYPE_HOOK) {
+            require(_hook == address(0), ERC7579HookModuleAlreadyPresent(_hook));
+            _hook = module;
+        }
+        super._installModule(moduleTypeId, module, initData);
+    }
+
+    /// @dev Uninstalls a module with support for hook modules. See {AccountERC7579-_uninstallModule}
+    function _uninstallModule(
+        uint256 moduleTypeId,
+        address module,
+        bytes memory deInitData
+    ) internal virtual override withHook {
+        if (moduleTypeId == MODULE_TYPE_HOOK) {
+            require(_hook == module, ERC7579Utils.ERC7579UninstalledModule(moduleTypeId, module));
+            _hook = address(0);
+        }
+        super._uninstallModule(moduleTypeId, module, deInitData);
+    }
+
+    /// @dev Hooked version of {AccountERC7579-_execute}.
+    function _execute(
+        Mode mode,
+        bytes calldata executionCalldata
+    ) internal virtual override withHook returns (bytes[] memory) {
+        return super._execute(mode, executionCalldata);
+    }
+
+    /// @dev Hooked version of {AccountERC7579-_fallback}.
+    function _fallback() internal virtual override withHook returns (bytes memory) {
+        return super._fallback();
+    }
+}

dev/env/node_modules/@openzeppelin/contracts/account/extensions/draft-ERC7821.sol

@@ -0,0 +1,70 @@
+// SPDX-License-Identifier: MIT
+// OpenZeppelin Contracts (last updated v5.4.0) (account/extensions/draft-ERC7821.sol)
+
+pragma solidity ^0.8.20;
+
+import {ERC7579Utils, Mode, CallType, ExecType, ModeSelector} from "../utils/draft-ERC7579Utils.sol";
+import {IERC7821} from "../../interfaces/draft-IERC7821.sol";
+import {Account} from "../Account.sol";
+
+/**
+ * @dev Minimal batch executor following ERC-7821.
+ *
+ * Only supports supports single batch mode (`0x01000000000000000000`). Does not support optional "opData".
+ *
+ * @custom:stateless
+ */
+abstract contract ERC7821 is IERC7821 {
+    using ERC7579Utils for *;
+
+    error UnsupportedExecutionMode();
+
+    /**
+     * @dev Executes the calls in `executionData` with no optional `opData` support.
+     *
+     * NOTE: Access to this function is controlled by {_erc7821AuthorizedExecutor}. Changing access permissions, for
+     * example to approve calls by the ERC-4337 entrypoint, should be implemented by overriding it.
+     *
+     * Reverts and bubbles up error if any call fails.
+     */
+    function execute(bytes32 mode, bytes calldata executionData) public payable virtual {
+        if (!_erc7821AuthorizedExecutor(msg.sender, mode, executionData))
+            revert Account.AccountUnauthorized(msg.sender);
+        if (!supportsExecutionMode(mode)) revert UnsupportedExecutionMode();
+        executionData.execBatch(ERC7579Utils.EXECTYPE_DEFAULT);
+    }
+
+    /// @inheritdoc IERC7821
+    function supportsExecutionMode(bytes32 mode) public view virtual returns (bool result) {
+        (CallType callType, ExecType execType, ModeSelector modeSelector, ) = Mode.wrap(mode).decodeMode();
+        return
+            callType == ERC7579Utils.CALLTYPE_BATCH &&
+            execType == ERC7579Utils.EXECTYPE_DEFAULT &&
+            modeSelector == ModeSelector.wrap(0x00000000);
+    }
+
+    /**
+     * @dev Access control mechanism for the {execute} function.
+     * By default, only the contract itself is allowed to execute.
+     *
+     * Override this function to implement custom access control, for example to allow the
+     * ERC-4337 entrypoint to execute.
+     *
+     * ```solidity
+     * function _erc7821AuthorizedExecutor(
+     *   address caller,
+     *   bytes32 mode,
+     *   bytes calldata executionData
+     * ) internal view virtual override returns (bool) {
+     *   return caller == address(entryPoint()) || super._erc7821AuthorizedExecutor(caller, mode, executionData);
+     * }
+     * ```
+     */
+    function _erc7821AuthorizedExecutor(
+        address caller,
+        bytes32 /* mode */,
+        bytes calldata /* executionData */
+    ) internal view virtual returns (bool) {
+        return caller == address(this);
+    }
+}