feat: add authentication and user management with Authentik integration

- Add PostgreSQL database with async SQLAlchemy
- Add Alembic migrations for schema management
- Add User, Role, UserPreferences, ApiKey models
- Add auth endpoints: /auth/me, /auth/users, /auth/users/sync-from-authentik
- Add token validation via Authentik userinfo endpoint
- Add bulk user sync from Authentik admin API
- Add database health check to diagnostics

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/main.py

@@ -9,11 +9,13 @@ from contextlib import asynccontextmanager
 from src.config import get_settings
 from src.logging_config import setup_logging, get_logger
 from src.models.ollama_client import get_ollama_client, close_ollama_client
+from src.db import get_database
 from src.controllers.infrastructure_controller import infrastructure_controller
 from src.controllers.tools_controller import tools_controller
 from src.controllers.health_controller import health_controller
 from src.controllers.static_controller import static_controller
 from src.controllers.housekeeping_controller import housekeeping_controller
+from src.auth.controller import auth_controller
 from src.security import initialize_oidc
 
 # Initialize settings
@@ -48,6 +50,14 @@ async def lifespan(app: FastAPI):
     else:
         logger.warning("✗ Ollama connection failed - AI features may not work")
 
+    # Check database connectivity
+    database = get_database()
+    db_healthy = await database.health_check()
+    if db_healthy:
+        logger.info("✓ Database connection successful")
+    else:
+        logger.warning("✗ Database connection failed - auth features may not work")
+
     # Initialize security (OIDC authentication)
     initialize_oidc(settings)
 
@@ -56,6 +66,7 @@ async def lifespan(app: FastAPI):
     # Shutdown
     logger.info("Shutting down application")
     await close_ollama_client()
+    await database.close()
 
 
 # Create FastAPI application
@@ -96,6 +107,7 @@ app.add_middleware(
 
 # Include controller routers
 app.include_router(health_controller.router)                   # / and /health
+app.include_router(auth_controller.router)                     # /auth/*
 app.include_router(tools_controller.router)                    # /tools/*
 app.include_router(infrastructure_controller.router)           # /infrastructure/*
 app.include_router(housekeeping_controller.router)             # /housekeeping/*