Address PR review feedback

- Replace plano.katanemo.com with planoai.dev in allowed hosts
- Add planoai.dev to OG route and blog layout allowlists
- Revert socket bind to 0.0.0.0 (intentional for port-in-use check)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

cli/planoai/main.py

@@ -45,7 +45,7 @@ def _is_port_in_use(port: int) -> bool:
 
     with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
         try:
-            s.bind(("127.0.0.1", port))
+            s.bind(("0.0.0.0", port))  # noqa: S104
             return False
         except OSError:
             return True