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/ethers/src.ts/abi/coders/null.ts

@@ -0,0 +1,28 @@
+import { Coder } from "./abstract-coder.js";
+import type { Reader, Writer } from "./abstract-coder.js";
+
+const Empty = new Uint8Array([ ]);
+
+/**
+ *  @_ignore
+ */
+export class NullCoder extends Coder {
+
+    constructor(localName: string) {
+        super("null", "", localName, false);
+    }
+
+    defaultValue(): null {
+        return null;
+    }
+
+    encode(writer: Writer, value: any): number {
+        if (value != null) { this._throwError("not null", value); }
+        return writer.writeBytes(Empty);
+    }
+
+    decode(reader: Reader): any {
+        reader.readBytes(0);
+        return null;
+    }
+}