fix: use current UTC timestamp for genesis blocks and fix lambda closure bugs

- Changed genesis block timestamp from hardcoded 2025-01-01 to datetime.now(timezone.utc)
- Fixes unified_genesis.py, poa.py genesis creation, and fallback genesis timestamp
- Fixed lambda closure bugs in session_factory by capturing chain_id with default parameter
- Removed localhost:8006 from default bootstrap peers (hub nodes create own genesis)
- Updated comments to reflect genesis timestamp change from deterministic to current time

apps/blockchain-node/scripts/unified_genesis.py

@@ -123,7 +123,7 @@ def create_genesis_wallet(password: str = None, chain_id: str = "ait-mainnet") -
 def create_genesis_block(chain_id: str, proposer: str, timestamp: datetime = None) -> Dict[str, Any]:
     """Create genesis block"""
     if not timestamp:
-        timestamp = datetime.fromisoformat("2025-01-01 00:00:00")
+        timestamp = datetime.now(timezone.utc)
     
     parent_hash = "0x00"
     genesis_hash = compute_block_hash(0, parent_hash, timestamp, chain_id)

apps/blockchain-node/src/aitbc_chain/consensus/poa.py

@@ -111,8 +111,7 @@ class PoAProposer:
 
     def _fetch_chain_head(self) -> Optional[Block]:
         """Fetch the current chain head block from the database."""
-        from ..database import session_scope
-        with session_scope(self._config.chain_id) as session:
+        with self._session_factory() as session:
             return session.exec(
                 select(Block).where(Block.chain_id == self._config.chain_id).order_by(Block.height.desc()).limit(1)
             ).first()
@@ -442,7 +441,7 @@ class PoAProposer:
                 
                 if genesis_hash and genesis_state_root:
                     # Create genesis block with RPC-provided data
-                    timestamp = datetime(2025, 1, 1, 0, 0, 0)
+                    timestamp = datetime.now(timezone.utc)
                     genesis = Block(
                         chain_id=self._config.chain_id,
                         height=0,
@@ -473,8 +472,8 @@ class PoAProposer:
             # Fall back to local genesis block creation
             self._logger.info(f"Creating genesis block locally for chain {self._config.chain_id}")
             
-            # Use a deterministic genesis timestamp so all nodes agree on the genesis block hash
-            timestamp = datetime(2025, 1, 1, 0, 0, 0)
+            # Use current timestamp for genesis block
+            timestamp = datetime.now(timezone.utc)
             block_hash = self._compute_block_hash(0, "0x00", timestamp)
             
             # Check if block with this hash already exists (duplicate check)
@@ -607,7 +606,7 @@ class PoAProposer:
                 peer_url = peer_url.replace("http://", "")
             peer_url = f"http://{peer_url}"
             trusted_peers.append(peer_url)
-        trusted_peers.append("http://localhost:8006")
+        # Don't add localhost as default bootstrap peer - hub nodes should create their own genesis
         
         self._logger.info(f"Attempting RPC bootstrap for genesis block from peers: {trusted_peers}")
         
@@ -647,7 +646,7 @@ class PoAProposer:
                 peer_url = peer_url.replace("http://", "")
             peer_url = f"http://{peer_url}"
             trusted_peers.append(peer_url)
-        trusted_peers.append("http://localhost:8006")
+        # Don't add localhost as default bootstrap peer - hub nodes should create their own genesis
         
         self._logger.info(f"Attempting RPC bootstrap from peers: {trusted_peers}")
         

apps/blockchain-node/src/aitbc_chain/main.py

@@ -138,7 +138,7 @@ class BlockchainNode:
 
     async def _ensure_genesis_for_chains(self) -> None:
         for chain_id in self._supported_chains():
-            proposer = PoAProposer(config=self._proposer_config(chain_id), session_factory=lambda: session_scope(chain_id))
+            proposer = PoAProposer(config=self._proposer_config(chain_id), session_factory=lambda cid=chain_id: session_scope(cid))
             await proposer._ensure_genesis_block()
 
     async def _setup_gossip_subscribers(self) -> None:
@@ -192,7 +192,7 @@ class BlockchainNode:
                                 import json
                                 block_data = json.loads(block_data)
                             logger.info(f"Importing block for chain {chain_id_param}: {block_data.get('height')}")
-                            sync = ChainSync(session_factory=lambda: session_scope(chain_id_param), chain_id=chain_id_param)
+                            sync = ChainSync(session_factory=lambda cid=chain_id_param: session_scope(cid), chain_id=chain_id_param)
                             res = sync.import_block(block_data, transactions=block_data.get("transactions"))
                             logger.info(f"Import result: accepted={res.accepted}, reason={res.reason}")
                             
@@ -322,7 +322,7 @@ class BlockchainNode:
             if chain_id in self._proposers:
                 continue
 
-            proposer = PoAProposer(config=self._proposer_config(chain_id), session_factory=lambda: session_scope(chain_id))
+            proposer = PoAProposer(config=self._proposer_config(chain_id), session_factory=lambda cid=chain_id: session_scope(cid))
             self._proposers[chain_id] = proposer
             asyncio.create_task(proposer.start())