Fix architecture issues from todolist

- Add documentation warnings for in-memory rate limiting and failed login attempts
- Consolidate duplicate health endpoints into api/health.py
- Fix CLI to use correct async rescan method names
- Update download.py and anime.py to use custom exception classes
- Add WebSocket room validation and rate limiting

src/server/controllers/health_controller.py

@@ -1,27 +0,0 @@
-"""
-Health check controller for monitoring and status endpoints.
-
-This module provides health check endpoints for application monitoring.
-"""
-from fastapi import APIRouter
-
-from src.config.settings import settings
-from src.server.utils.dependencies import _series_app
-
-router = APIRouter(prefix="/health", tags=["health"])
-
-
-@router.get("")
-async def health_check():
-    """Health check endpoint for monitoring.
-    
-    This endpoint does not depend on anime_directory configuration
-    and should always return 200 OK for basic health monitoring.
-    """
-    return {
-        "status": "healthy",
-        "service": "aniworld-api",
-        "version": "1.0.0",
-        "series_app_initialized": _series_app is not None,
-        "anime_directory_configured": bool(settings.anime_directory)
-    }