refactor(MessageManager): enhance conversation list handling and integrate local source fallback

- Update MessageManager to support both remote and local conversation list sources, improving data retrieval and offline capabilities.
- Refactor hooks and components to utilize the new MessageManager structure, ensuring seamless integration of cursor pagination and local caching.
- Introduce new types and methods for better management of conversation data and loading states.
- Modify MessageListScreen to leverage the updated hooks for fetching conversations, enhancing user experience with improved loading and pagination handling.

src/screens/message/MessageListScreen.tsx

@@ -31,13 +31,19 @@ import { useBottomTabBarHeight } from '@react-navigation/bottom-tabs';
 import { MaterialCommunityIcons } from '@expo/vector-icons';
 import { colors, spacing, fontSizes, shadows, borderRadius } from '../../theme';
 import { ConversationResponse, UserDTO, MessageResponse, extractTextFromSegments, extractTextFromSegmentsAsync, MessageSegment } from '../../types/dto';
-import { authService, messageService } from '../../services';
+import { authService } from '../../services';
 import { useUserStore, useAuthStore } from '../../stores';
-// 【新架构】使用MessageManager hooks
-import { messageManager, useMessageListRefresh, useCreateConversation, useUnreadCount, useMarkAsRead } from '../../stores';
+// 【新架构】使用MessageManager hooks（会话列表数据源自 MessageManager 游标同步）
+import {
+  messageManager,
+  useMessageListRefresh,
+  useCreateConversation,
+  useUnreadCount,
+  useMarkAsRead,
+  useMessageManagerConversations,
+} from '../../stores';
 import { Avatar, Text, EmptyState, ResponsiveContainer } from '../../components/common';
 import { useResponsive, useBreakpointGTE } from '../../hooks/useResponsive';
-import { useCursorPagination } from '../../hooks/useCursorPagination';
 import { RootStackParamList, MessageStackParamList } from '../../navigation/types';
 import { getUserCache } from '../../services/database';
 // 导入 EmbeddedChat 组件用于桌面端双栏布局
@@ -162,24 +168,14 @@ export const MessageListScreen: React.FC = () => {
   const { isDesktop, isTablet, width } = useResponsive();
   const isWideScreen = useBreakpointGTE('lg');
 
-  // 【游标分页】使用 useCursorPagination hook 获取会话列表
+  // 会话列表：MessageManager 统一游标拉取与合并，与已读/角标同源
   const {
-    list: conversationList,
+    conversations: conversationList,
     isLoading,
-    isRefreshing,
     hasMore,
     loadMore,
     refresh,
-    error: paginationError,
-  } = useCursorPagination(
-    async ({ cursor, pageSize }) => {
-      return await messageService.getConversationsCursor({
-        cursor,
-        page_size: pageSize,
-      });
-    },
-    { pageSize: 20 }
-  );
+  } = useMessageManagerConversations();
 
   // 使用 MessageManager 获取未读数和系统通知数
   const { totalUnreadCount, systemUnreadCount } = useUnreadCount();