refactor: update database schema and fix chain_id handling across components

- Add new Transaction fields: nonce, value, fee, status, timestamp, tx_metadata
- Add block_metadata field to Block model
- Remove account_type and metadata fields from Account creation
- Simplify contract deployment transaction structure
- Fix chain_id hardcoding in PoA proposer and RPC router
- Update config to use /opt/aitbc/.env path with extra="ignore"
- Switch from starlette.broadcast to broadcaster module
- Update CLI

test_broadcaster.py

@@ -0,0 +1,16 @@
+import asyncio
+from broadcaster import Broadcast
+
+async def main():
+    broadcast = Broadcast("redis://localhost:6379")
+    await broadcast.connect()
+    print("connected")
+    async with broadcast.subscribe("test") as sub:
+        print("subscribed")
+        await broadcast.publish("test", "hello")
+        async for msg in sub:
+            print("msg:", msg.message)
+            break
+    await broadcast.disconnect()
+
+asyncio.run(main())