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_mempool5.py

@@ -0,0 +1,17 @@
+with open("/home/oib/windsurf/aitbc/apps/blockchain-node/src/aitbc_chain/rpc/router.py", "r") as f:
+    content = f.read()
+
+# Fix DatabaseMempool.add() call in router.py - the problem was `mempool.add(tx_dict, chain_id)` which is 3 positional arguments (self, tx, chain_id).
+# Wait, `def add(self, tx: Dict[str, Any], chain_id: str = "ait-devnet") -> str:`
+# `mempool.add(tx_dict, chain_id)` shouldn't raise "takes 2 positional arguments but 3 were given" unless `get_mempool()` is returning `InMemoryMempool` instead of `DatabaseMempool`.
+
+# Let's check init_mempool in main.py, it uses MEMPOOL_BACKEND from config.
+# If MEMPOOL_BACKEND="database" then it should be DatabaseMempool.
+
+content = content.replace(
+    "tx_hash = mempool.add(tx_dict, chain_id)",
+    "tx_hash = mempool.add(tx_dict, chain_id=chain_id)" # try keyword
+)
+
+with open("/home/oib/windsurf/aitbc/apps/blockchain-node/src/aitbc_chain/rpc/router.py", "w") as f:
+    f.write(content)