chore: remove configuration files and enhance blockchain explorer with advanced search, analytics, and export features

- Delete .aitbc.yaml.example CLI configuration template
- Delete .lycheeignore link checker exclusion rules
- Delete .nvmrc Node.js version specification
- Add advanced search panel with filters for address, amount range, transaction type, time range, and validator
- Add analytics dashboard with transaction volume, active addresses, and block time metrics
- Add Chart.js integration

dev/scripts/patch_poa_propose.py

@@ -0,0 +1,14 @@
+import re
+with open("/home/oib/windsurf/aitbc/apps/blockchain-node/src/aitbc_chain/consensus/poa.py", "r") as f:
+    content = f.read()
+
+# Fix the head query to filter by chain_id in _propose_block
+content = content.replace(
+    """        with self._session_factory() as session:
+            head = session.exec(select(Block).order_by(Block.height.desc()).limit(1)).first()""",
+    """        with self._session_factory() as session:
+            head = session.exec(select(Block).where(Block.chain_id == self._config.chain_id).order_by(Block.height.desc()).limit(1)).first()"""
+)
+
+with open("/home/oib/windsurf/aitbc/apps/blockchain-node/src/aitbc_chain/consensus/poa.py", "w") as f:
+    f.write(content)