feat (状态仓库)：对接后端会话删除接口

· 将会话删除逻辑迁移至 chatStore.deleteSession，封装为异步方法
· 会话列表（SessionList）中移除直接调用服务的写法，统一使用仓库提供的方法
· 增加异常捕获处理：接口调用失败时，提供兜底方案清理本地状态
· 实现批量删除功能，追踪每条会话的删除成功 / 失败结果
· 更新 ChatStoreState 类型声明，适配异步 deleteSession 方法
· 简化用户提示文案，统一删除流程反馈话术
· 保证逻辑顺序：优先尝试调用后端执行文档清理，成功后再移除本地状态

src/components/SessionList/SessionList.tsx

@@ -180,14 +180,10 @@ const SessionList: React.FC<SessionListProps> = ({ onSessionLoad }) => {
     e.stopPropagation();
     
     try {
-      // 从后端删除会话文档
-      const { deleteSessionHistory } = await import('../../services/sessionService');
-      const result = await deleteSessionHistory(sessionId);
+      // 调用 chatStore 的 deleteSession (内部会调用后端 API)
+      await deleteSession(sessionId);
       
-      // 从本地状态删除
-      deleteSession(sessionId);
-      
-      antdMessage.success(`成功删除会话，共删除 ${result.data.deletedCount} 个文档`);
+      antdMessage.success('成功删除会话及其关联的所有文档');
     } catch (error) {
       console.error('删除会话失败:', error);
       antdMessage.error('删除会话失败，请重试');
@@ -236,26 +232,31 @@ const SessionList: React.FC<SessionListProps> = ({ onSessionLoad }) => {
     }
 
     try {
-      // 从后端批量删除
-      const { deleteSessions } = await import('../../services/sessionService');
-      const result = await deleteSessions(Array.from(selectedSessionIds));
+      let successCount = 0;
+      let failedCount = 0;
       
-      // 从本地状态删除成功的会话
-      selectedSessionIds.forEach(sessionId => {
-        deleteSession(sessionId);
-      });
+      // 逐个调用 deleteSession (内部会调用后端 API)
+      for (const sessionId of Array.from(selectedSessionIds)) {
+        try {
+          await deleteSession(sessionId);
+          successCount++;
+        } catch (error) {
+          console.error(`删除会话 ${sessionId} 失败:`, error);
+          failedCount++;
+        }
+      }
 
       // Reset selection state
       setSelectedSessionIds(new Set());
       setIsSelectionMode(false);
       
-      if (result.failedCount > 0) {
+      if (failedCount > 0) {
         antdMessage.warning(
-          `删除完成：成功 ${result.successCount} 个，失败 ${result.failedCount} 个`
+          `删除完成：成功 ${successCount} 个，失败 ${failedCount} 个`
         );
       } else {
         antdMessage.success(
-          `成功删除 ${result.successCount} 个会话，共删除 ${result.totalDeletedDocuments} 个文档`
+          `成功删除 ${successCount} 个会话及其关联的所有文档`
         );
       }
     } catch (error) {

src/stores/chatStore.ts

@@ -230,24 +230,51 @@ export const useChatStore = create<ChatStoreState>((set, get) => ({
   /**
    * Delete a session by ID
    * 
+   * ⭐ 修改: 调用后端 API 删除会话及其关联的所有文档
+   * 
    * @param sessionId - Session ID to delete
    */
-  deleteSession: (sessionId: string) => {
-    set((state) => {
-      const updatedSessions = state.sessions.filter((s) => s.id !== sessionId);
-      saveSessionsToStorage(updatedSessions);
-      
-      // If deleting current session, clear current session
-      const newCurrentSessionId = state.currentSessionId === sessionId 
-        ? null 
-        : state.currentSessionId;
+  deleteSession: async (sessionId: string) => {
+    try {
+      // 调用后端 API 删除会话的所有文档
+      const { deleteSessionHistory } = await import('../services/sessionService');
+      await deleteSessionHistory(sessionId);
       
-      return {
-        currentSessionId: newCurrentSessionId,
-        sessions: updatedSessions,
-        messages: newCurrentSessionId === null ? [] : state.messages,
-      };
-    });
+      // 删除成功后,从本地状态中移除
+      set((state) => {
+        const updatedSessions = state.sessions.filter((s) => s.id !== sessionId);
+        saveSessionsToStorage(updatedSessions);
+        
+        // If deleting current session, clear current session
+        const newCurrentSessionId = state.currentSessionId === sessionId 
+          ? null 
+          : state.currentSessionId;
+        
+        return {
+          currentSessionId: newCurrentSessionId,
+          sessions: updatedSessions,
+          messages: newCurrentSessionId === null ? [] : state.messages,
+        };
+      });
+    } catch (error) {
+      console.error('删除会话失败:', error);
+      // 即使后端删除失败,也从本地状态中移除(因为可能是网络问题)
+      set((state) => {
+        const updatedSessions = state.sessions.filter((s) => s.id !== sessionId);
+        saveSessionsToStorage(updatedSessions);
+        
+        const newCurrentSessionId = state.currentSessionId === sessionId 
+          ? null 
+          : state.currentSessionId;
+        
+        return {
+          currentSessionId: newCurrentSessionId,
+          sessions: updatedSessions,
+          messages: newCurrentSessionId === null ? [] : state.messages,
+        };
+      });
+      throw error; // 重新抛出错误供调用者处理
+    }
   },
 
   /**

src/types/store.ts

@@ -58,8 +58,8 @@ export interface ChatStoreState {
   createSession: () => string;
   /** Load an existing session by ID */
   loadSession: (sessionId: string) => void;
-  /** Delete a session by ID */
-  deleteSession: (sessionId: string) => void;
+  /** Delete a session by ID (calls backend API to delete documents) */
+  deleteSession: (sessionId: string) => Promise<void>;
   /** Send a message to AI and get response */
   sendMessage: (content: string) => Promise<void>;
   /** Add a message to the current session */