Add database initialization for first superuser setup

Introduced a script to create the initial superuser during app startup if none exists. Updated the entrypoint to call this script and added stricter logging for passlib. Adjusted .env.template for a stronger default superuser password.

backend/app/core/auth.py

@@ -1,4 +1,6 @@
-# app/core/auth.py
+import logging
+logging.getLogger('passlib').setLevel(logging.ERROR)
+
 from datetime import datetime, timedelta, timezone
 from typing import Any, Dict, Optional, Union
 import uuid