fix: 修复proxy_service和account_service中不当的顶层import

- proxy_service.py: 将requests和WhitelistManager改为函数内延迟import，
  避免启动时加载不需要的依赖；移除未使用的get_exit_ip_via_proxy导入
- account_service.py: 移除未使用的func、joinedload、AuditLog、
  user_has_permission顶层导入

web/frontend/src/hooks/usePermissions.ts

@@ -0,0 +1,23 @@
+import { useCallback, useMemo } from 'react';
+import { getUser, type AuthUser } from '../store/auth';
+
+export function usePermissions(userOverride?: AuthUser | null) {
+  const user = userOverride === undefined ? getUser() : userOverride;
+  const permissions = useMemo(() => user?.permissions ?? [], [user]);
+
+  const permissionSet = useMemo(() => new Set(permissions), [permissions]);
+
+  const can = useCallback((permission: string) => permissionSet.has(permission), [permissionSet]);
+
+  const canAny = useCallback(
+    (items: string[]) => items.some((permission) => permissionSet.has(permission)),
+    [permissionSet],
+  );
+
+  return {
+    user,
+    can,
+    canAny,
+    permissions,
+  };
+}

web/frontend/src/hooks/useWebSocketLogs.ts

@@ -0,0 +1,102 @@
+import { useCallback, useEffect, useRef, useState } from 'react';
+
+export interface RealtimeLog {
+  level: string;
+  message: string;
+}
+
+interface ConnectOptions {
+  clear?: boolean;
+  onClose?: () => void;
+  onError?: () => void;
+  onResult?: () => void;
+}
+
+function toWebSocketUrl(pathOrUrl: string): string {
+  if (pathOrUrl.startsWith('ws://') || pathOrUrl.startsWith('wss://')) {
+    return pathOrUrl;
+  }
+  const protocol = window.location.protocol === 'https:' ? 'wss' : 'ws';
+  const path = pathOrUrl.startsWith('/') ? pathOrUrl : `/${pathOrUrl}`;
+  return `${protocol}://${window.location.host}${path}`;
+}
+
+export function useWebSocketLogs() {
+  const [logs, setLogs] = useState<RealtimeLog[]>([]);
+  const [connected, setConnected] = useState(false);
+  const wsRef = useRef<WebSocket | null>(null);
+  const callbacksRef = useRef<ConnectOptions>({});
+  const suppressCloseRef = useRef(false);
+
+  const clearLogs = useCallback(() => {
+    setLogs([]);
+  }, []);
+
+  const close = useCallback((notify = false) => {
+    if (!wsRef.current) {
+      setConnected(false);
+      return;
+    }
+    suppressCloseRef.current = !notify;
+    wsRef.current.close();
+    wsRef.current = null;
+    setConnected(false);
+  }, []);
+
+  const connect = useCallback((pathOrUrl: string, options: ConnectOptions = {}) => {
+    close(false);
+    suppressCloseRef.current = false;
+    callbacksRef.current = options;
+    if (options.clear ?? true) {
+      setLogs([]);
+    }
+
+    const ws = new WebSocket(toWebSocketUrl(pathOrUrl));
+    wsRef.current = ws;
+    setConnected(true);
+
+    ws.onmessage = (event) => {
+      try {
+        const msg = JSON.parse(event.data) as RealtimeLog;
+        if (msg.level === 'heartbeat') return;
+        if (msg.level === 'result') {
+          callbacksRef.current.onResult?.();
+          return;
+        }
+        setLogs((prev) => [...prev, msg]);
+      } catch {
+        setLogs((prev) => [...prev, { level: 'info', message: String(event.data) }]);
+      }
+    };
+
+    ws.onclose = () => {
+      const isCurrent = wsRef.current === ws;
+      const shouldNotify = isCurrent && !suppressCloseRef.current;
+      if (isCurrent) {
+        wsRef.current = null;
+        setConnected(false);
+        suppressCloseRef.current = false;
+      }
+      if (shouldNotify) {
+        callbacksRef.current.onClose?.();
+      }
+    };
+
+    ws.onerror = () => {
+      setConnected(false);
+      callbacksRef.current.onError?.();
+    };
+  }, [close]);
+
+  useEffect(() => () => {
+    close(false);
+  }, [close]);
+
+  return {
+    logs,
+    connected,
+    clearLogs,
+    connect,
+    close,
+  };
+}