feat: fpw plugins, validation/crawl perf, WS stats, test DB isolation

- Add Free_Proxy_Website-style fpw_* plugins and register them
- Per-plugin crawl timeout (crawl_timeout_seconds=120); remove global crawl_timeout setting
- Validator: fix connect vs total timeout on save; SOCKS session LRU cache; drop redundant semaphore
- Validation handler uses single DB connection; batch upsert after crawl; WorkerPool put_nowait
- Remove unused max_retries from settings API/UI; settings maintenance SQL + init_db cleanup of deprecated keys
- WebSocket dashboard stats; ProxyList pool_filter and API alignment
- POST /api/proxies/delete-one for IPv6-safe deletes; task poll stops on 404
- pytest uses PROXYPOOL_DB_PATH=db/proxies.test.sqlite so tests do not wipe production DB
- .gitignore: explicit proxies.test.sqlite patterns; fix plugin_service ValidationException import

Made-with: Cursor

app/api/routes/__init__.py

@@ -1,9 +1,10 @@
 """路由包"""
 from fastapi import APIRouter
-from app.api.routes import proxies, plugins, scheduler, settings, tasks
+from app.api.routes import proxies, plugins, scheduler, settings, tasks, ws
 
 api_router = APIRouter()
 api_router.include_router(proxies.router)
+api_router.include_router(ws.router)
 api_router.include_router(plugins.router)
 api_router.include_router(scheduler.router)
 api_router.include_router(settings.router)