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/presentation/hooks/responsive/index.ts

@@ -0,0 +1,66 @@
+/**
+ * 响应式 Hooks 统一导出
+ * Responsive Hooks Index
+ * 
+ * 提供完整的响应式设计解决方案，包括：
+ * - 断点检测 (useBreakpoint)
+ * - 屏幕尺寸 (useScreenSize, useWindowDimensions)
+ * - 响应式值 (useResponsiveValue, useResponsiveStyle)
+ * - 方向检测 (useOrientation)
+ * - 平台检测 (usePlatform)
+ * - 媒体查询 (useMediaQuery)
+ * - 列数计算 (useColumnCount)
+ * - 间距计算 (useResponsiveSpacing)
+ * - 断点检查 (useBreakpointGTE, useBreakpointLT, useBreakpointBetween)
+ */
+
+// ==================== 核心 Hooks ====================
+export { useWindowDimensions, useScreenSize } from './useScreenSize';
+export { 
+  useBreakpoint, 
+  useFineBreakpoint,
+  useBreakpointGTE, 
+  useBreakpointLT, 
+  useBreakpointBetween,
+} from './useBreakpoint';
+export { useResponsiveValue, useResponsiveStyle } from './useResponsiveValue';
+export { useOrientation } from './useOrientation';
+export { usePlatform } from './usePlatform';
+export { useMediaQuery } from './useMediaQuery';
+export { useColumnCount } from './useColumnCount';
+export { useResponsiveSpacing } from './useResponsiveSpacing';
+
+// ==================== 工具函数 ====================
+export {
+  getBreakpoint,
+  getFineBreakpoint,
+  isBreakpointGTE,
+  isBreakpointLT,
+  isBreakpointBetween,
+} from './useBreakpoint';
+
+// ==================== 类型 ====================
+export type {
+  BreakpointKey,
+  FineBreakpointKey,
+  BreakpointValue,
+  ResponsiveValue,
+  Orientation,
+  PlatformInfo,
+  ScreenSize,
+  MediaQueryOptions,
+} from './types';
+
+export {
+  BREAKPOINTS,
+  FINE_BREAKPOINTS,
+} from './types';
+
+// 兼容层类型
+export type { ResponsiveInfo } from './useResponsive';
+
+// ==================== 向后兼容 ====================
+export { useResponsive, useLegacyResponsive } from './useResponsive';
+
+// 默认导出
+export { useScreenSize as default } from './useScreenSize';