refactor: 架构重构 - 解耦过度耦合模块

主要改动:
1. 创建乐观更新工具函数 (optimisticUpdate.ts)
   - 消除 userStore.ts 中的重复代码

2. 拆分 useResponsive.ts (485行 -> 12个专注模块)
   - useBreakpoint: 断点检测
   - useOrientation: 方向检测
   - usePlatform: 平台检测
   - useScreenSize: 屏幕尺寸
   - useResponsiveValue: 响应式值
   - useResponsiveStyle: 响应式样式
   - useMediaQuery: 媒体查询
   - useColumnCount: 列数计算
   - useResponsiveSpacing: 响应式间距

3. 整理数据层 (Repository 层)
   - ApiDataSource: API数据源
   - LocalDataSource: 本地数据源
   - CacheDataSource: 缓存数据源
   - MessageRepository: 消息仓库

4. 重构 messageManager.ts (2194行 -> 4个模块)
   - MessageStateManager: 状态管理
   - WebSocketMessageHandler: WebSocket处理
   - MessageSyncService: 消息同步
   - ReadReceiptManager: 已读管理

5. 导航解耦 (MainNavigator.tsx: 1118行 -> 100行)
   - 创建 NavigationService 解耦层
   - 拆分多个 Navigator 组件

架构改进:
- 单一职责原则: 每个模块职责明确
- 依赖倒置: 通过接口解耦
- 代码复用: 工具函数可被多处使用
- 可测试性: 各模块可独立测试

src/infrastructure/navigation/hooks/useNavigationState.ts

@@ -0,0 +1,60 @@
+/**
+ * 导航状态管理 Hook
+ * 管理导航相关状态，如当前路由、导航历史等
+ */
+
+import { useState, useCallback, useEffect } from 'react';
+import { useNavigationState as useRNNavigationState, Route } from '@react-navigation/native';
+import type { RootStackParamList } from '../../../navigation/types';
+
+type TabName = 'HomeTab' | 'MessageTab' | 'ScheduleTab' | 'ProfileTab';
+
+interface NavigationState {
+  currentTab: TabName;
+  isCollapsed: boolean;
+  isReady: boolean;
+}
+
+interface NavigationActions {
+  setCurrentTab: (tab: TabName) => void;
+  toggleCollapse: () => void;
+  setIsReady: (ready: boolean) => void;
+}
+
+/**
+ * 导航状态管理 Hook
+ */
+export function useNavigationState(): NavigationState & NavigationActions {
+  const [currentTab, setCurrentTab] = useState<TabName>('HomeTab');
+  const [isCollapsed, setIsCollapsed] = useState(false);
+  const [isReady, setIsReady] = useState(false);
+
+  const toggleCollapse = useCallback(() => {
+    setIsCollapsed(prev => !prev);
+  }, []);
+
+  return {
+    currentTab,
+    isCollapsed,
+    isReady,
+    setCurrentTab,
+    toggleCollapse,
+    setIsReady,
+  };
+}
+
+/**
+ * 获取当前路由名称
+ */
+export function useCurrentRouteName(): string | null {
+  const routeName = useRNNavigationState(state => state?.routes[state.index]?.name ?? null);
+  return routeName;
+}
+
+/**
+ * 检查是否在指定路由
+ */
+export function useIsRoute(routeName: keyof RootStackParamList): boolean {
+  const currentRoute = useCurrentRouteName();
+  return currentRoute === routeName;
+}