feat: implement QR code scan login system with admin control

- Add scan login service with Redis-based token management
- Add scan login API routes for token generation and validation
- Add QRCodeLogin component for PC-side QR code display
- Add EntryQRCode component for mass login scenarios
- Add ScanLoginView for mobile-side login form
- Add localStorage persistence for user identity
- Add logout functionality to mobile client
- Add auto-redirect for logged-in users
- Add admin console control for QR code display on big screen
- Add socket event forwarding from admin to screen display

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

packages/client-mobile/src/stores/connection.ts

@@ -14,6 +14,31 @@ import { CONFIG } from '@gala/shared/constants';
 
 type GalaSocket = Socket<ServerToClientEvents, ClientToServerEvents>;
 
+// LocalStorage keys
+const STORAGE_KEYS = {
+  USER_ID: 'gala_user_id',
+  USER_NAME: 'gala_user_name',
+  DEPARTMENT: 'gala_department',
+};
+
+// Helper functions for localStorage
+function loadFromStorage<T>(key: string, defaultValue: T): T {
+  try {
+    const stored = localStorage.getItem(key);
+    return stored ? JSON.parse(stored) : defaultValue;
+  } catch {
+    return defaultValue;
+  }
+}
+
+function saveToStorage(key: string, value: unknown): void {
+  try {
+    localStorage.setItem(key, JSON.stringify(value));
+  } catch (e) {
+    console.warn('[Storage] Failed to save:', e);
+  }
+}
+
 export const useConnectionStore = defineStore('connection', () => {
   // State - use shallowRef for socket to avoid deep reactivity issues
   const socket = shallowRef<GalaSocket | null>(null);
@@ -23,9 +48,9 @@ export const useConnectionStore = defineStore('connection', () => {
   const lastPingTime = ref<number>(0);
   const latency = ref<number>(0);
   const reconnectAttempts = ref(0);
-  const userId = ref<string | null>(null);
-  const userName = ref<string | null>(null);
-  const department = ref<string | null>(null);
+  const userId = ref<string | null>(loadFromStorage(STORAGE_KEYS.USER_ID, null));
+  const userName = ref<string | null>(loadFromStorage(STORAGE_KEYS.USER_NAME, null));
+  const department = ref<string | null>(loadFromStorage(STORAGE_KEYS.DEPARTMENT, null));
   const votedCategories = ref<VoteCategory[]>([]);
 
   // Computed
@@ -69,10 +94,12 @@ export const useConnectionStore = defineStore('connection', () => {
       isConnecting.value = false;
       reconnectAttempts.value = 0;
 
-      // Auto-generate userId if not set
+      // Auto-generate userId if not set (and save to localStorage)
       if (!userId.value) {
         userId.value = `user_${Date.now()}_${Math.random().toString(36).slice(2, 9)}`;
         userName.value = '访客';
+        saveToStorage(STORAGE_KEYS.USER_ID, userId.value);
+        saveToStorage(STORAGE_KEYS.USER_NAME, userName.value);
       }
 
       // Join with user info
@@ -217,19 +244,43 @@ export const useConnectionStore = defineStore('connection', () => {
   }
 
   /**
-   * Set user info
+   * Set user info (and persist to localStorage)
    */
   function setUser(id: string, name: string, dept: string) {
     userId.value = id;
     userName.value = name;
     department.value = dept;
 
+    // Persist to localStorage
+    saveToStorage(STORAGE_KEYS.USER_ID, id);
+    saveToStorage(STORAGE_KEYS.USER_NAME, name);
+    saveToStorage(STORAGE_KEYS.DEPARTMENT, dept);
+
     // Rejoin if already connected
     if (socket.value?.connected) {
       joinRoom();
     }
   }
 
+  /**
+   * Logout and clear stored user info
+   */
+  function logout() {
+    // Clear state
+    userId.value = null;
+    userName.value = null;
+    department.value = null;
+    votedCategories.value = [];
+
+    // Clear localStorage
+    localStorage.removeItem(STORAGE_KEYS.USER_ID);
+    localStorage.removeItem(STORAGE_KEYS.USER_NAME);
+    localStorage.removeItem(STORAGE_KEYS.DEPARTMENT);
+
+    // Disconnect socket
+    disconnect();
+  }
+
   /**
    * Add voted category
    */
@@ -274,6 +325,7 @@ export const useConnectionStore = defineStore('connection', () => {
     // Actions
     connect,
     disconnect,
+    logout,
     setUser,
     addVotedCategory,
     requestSync,