refactor(core): optimize state management and component rendering performance

Improve application stability and performance by optimizing Zustand store usage, implementing memoization patterns, and introducing persistent authentication.

- **State Management**:
  - Refactor Zustand selectors to use `useShallow` and `getState()` to prevent unnecessary re-renders and infinite loops in hooks.
  - Implement `persist` middleware for `authStore` to maintain user sessions across restarts.
  - Introduce `buildStateCached` in `themeStore` to reduce redundant theme object computations.
- **Performance & Rendering**:
  - Implement `useMemo` for stable object/array references in `ImageGallery` and list components to prevent expensive re-renders.
  - Replace inline arrow functions with `useCallback` in complex screens like `ChatScreen` and `MessageListScreen`.
  - Optimize `FlashList` usage by providing stable `key` and `extraData` props.
- **Architecture**:
  - Decouple unread count fetching by introducing `useUnreadCountQuery` (React Query) for better caching and synchronization.
  - Add `useChannels` hook to centralize channel data fetching.
  - Refine `SessionGate` logic to allow immediate rendering of authenticated users while verifying in the background.

src/stores/message/hooks.ts

@@ -16,6 +16,7 @@ import { useShallow } from 'zustand/react/shallow';
 import { ConversationResponse, MessageResponse, MessageSegment } from '../../types/dto';
 import { messageManager } from './MessageManager';
 import { useMessageStore } from './store';
+import { useUnreadCountQuery } from '../../hooks/useUnreadCount';
 
 // ==================== useConversations - 获取会话列表 ====================
 
@@ -43,16 +44,19 @@ export function useConversations(): UseConversationsReturn {
       console.error('[useConversations] 初始化失败:', error);
     });
 
-    // 冷启动兜底：延迟做一次强制刷新，避免首次因时序问题拿到空列表
-    const coldStartSyncTimer = setTimeout(() => {
-      messageManager.refreshConversations(true, 'hooks-initial-refresh').catch(error => {
-        console.error('[useConversations] 冷启动强制刷新失败:', error);
-      });
-    }, 1200);
+    // 仅在首次初始化时做一次冷启动兜底刷新，避免每次挂载都触发
+    const store = useMessageStore.getState();
+    if (!store.isInitialized) {
+      const coldStartSyncTimer = setTimeout(() => {
+        messageManager.refreshConversations(true, 'hooks-initial-refresh').catch(error => {
+          console.error('[useConversations] 冷启动强制刷新失败:', error);
+        });
+      }, 1200);
 
-    return () => {
-      clearTimeout(coldStartSyncTimer);
-    };
+      return () => {
+        clearTimeout(coldStartSyncTimer);
+      };
+    }
   }, []);
 
   // 监听 hasMore 变化
@@ -249,15 +253,11 @@ interface UseUnreadCountReturn {
  * 使用 Zustand selector 直接订阅未读数变化
  */
 export function useUnreadCount(): UseUnreadCountReturn {
-  // 使用 Zustand selector 直接订阅未读数
+  // Use React Query for fetching (caching + auto-refetch), Zustand selectors for reading
+  useUnreadCountQuery();
   const totalUnreadCount = useMessageStore(state => state.totalUnreadCount);
   const systemUnreadCount = useMessageStore(state => state.systemUnreadCount);
 
-  useEffect(() => {
-    // 初始化时获取最新未读数
-    messageManager.fetchUnreadCount();
-  }, []);
-
   return {
     totalUnreadCount,
     systemUnreadCount,
@@ -271,14 +271,11 @@ export function useUnreadCount(): UseUnreadCountReturn {
  * 使用 Zustand selector 直接订阅
  */
 export function useTotalUnreadCount(): number {
+  // Use React Query for fetching, Zustand selectors for reading
+  useUnreadCountQuery();
   const totalUnreadCount = useMessageStore(state => state.totalUnreadCount);
   const systemUnreadCount = useMessageStore(state => state.systemUnreadCount);
 
-  useEffect(() => {
-    // 初始化时获取最新未读数
-    messageManager.fetchUnreadCount();
-  }, []);
-
   return totalUnreadCount + systemUnreadCount;
 }