feat: SuperAdmin bootstrap, i18n sync fix and AssetAssignment ORM fix

- Fixed AttributeError in User model (added region_code, preferred_language)
- Fixed InvalidRequestError in AssetAssignment (added organization relationship)
- Configured STATIC_DIR for translation sync
- Applied Alembic migrations for user schema updates

backend/app/core/config.py

@@ -1,10 +1,16 @@
 import os
+from pathlib import Path
 from typing import Any, Optional
 from pydantic_settings import BaseSettings, SettingsConfigDict
 from sqlalchemy import text
 from sqlalchemy.ext.asyncio import AsyncSession
 
 class Settings(BaseSettings):
+    # --- Paths (ÚJ SZEKCIÓ) ---
+    # Meghatározzuk a projekt gyökérmappáját és a statikus fájlok helyét
+    BASE_DIR: Path = Path(__file__).resolve().parent.parent.parent
+    STATIC_DIR: str = os.path.join(str(BASE_DIR), "static")
+
     # --- General ---
     PROJECT_NAME: str = "Traffic Ecosystem SuperApp"
     VERSION: str = "1.0.0"
@@ -16,8 +22,7 @@ class Settings(BaseSettings):
     ALGORITHM: str = "HS256"
     ACCESS_TOKEN_EXPIRE_MINUTES: int = 60 * 24 * 7 # 7 nap
 
-    # --- Initial Admin (ÚJ SZEKCIÓ) ---
-    # Ezeket a .env-ből fogja venni
+    # --- Initial Admin ---
     INITIAL_ADMIN_EMAIL: str = "admin@servicefinder.hu"
     INITIAL_ADMIN_PASSWORD: str = "Admin123!"