feat: 对话历史页面租户分组展示功能

- 新增 ConversationHistoryManager.get_tenant_summary() 按租户聚合会话统计
- get_sessions_paginated() 和 get_conversation_analytics() 增加 tenant_id 过滤
- 新增 GET /api/conversations/tenants 租户汇总端点
- sessions 和 analytics API 端点支持 tenant_id 查询参数
- 前端实现租户卡片列表视图和租户详情会话表格视图
- 实现面包屑导航、搜索范围限定、统计面板上下文切换
- 会话删除后自动检测空租户并返回列表视图
- dashboard.html 添加租户视图 DOM 容器
- 交互模式与知识库租户分组视图保持一致

src/dialogue/conversation_history.py

@@ -14,7 +14,7 @@ from ..core.database import db_manager
 from ..core.models import Conversation, WorkOrder, WorkOrderSuggestion, KnowledgeEntry, ChatSession
 from ..core.redis_manager import redis_manager
 from src.config.unified_config import get_config
-from sqlalchemy import and_, or_, desc
+from sqlalchemy import and_, or_, desc, func, case
 
 logger = logging.getLogger(__name__)
 
@@ -634,7 +634,8 @@ class ConversationHistoryManager:
     def get_conversation_analytics(
         self,
         work_order_id: Optional[int] = None,
-        days: int = 7
+        days: int = 7,
+        tenant_id: Optional[str] = None
     ) -> Dict[str, Any]:
         """获取对话分析数据（包含AI建议统计）"""
         try:
@@ -652,6 +653,8 @@ class ConversationHistoryManager:
                 conv_query = session.query(Conversation)
                 if work_order_id:
                     conv_query = conv_query.filter(Conversation.work_order_id == work_order_id)
+                if tenant_id is not None:
+                    conv_query = conv_query.filter(Conversation.tenant_id == tenant_id)
                 
                 conversations = conv_query.filter(
                     Conversation.timestamp >= cutoff_date
@@ -718,6 +721,49 @@ class ConversationHistoryManager:
             logger.error(f"获取对话分析数据失败: {e}")
             return {}
 
+    # ==================== 租户汇总方法 ====================
+
+    def get_tenant_summary(self) -> List[Dict[str, Any]]:
+        """
+        按 tenant_id 聚合 ChatSession，返回租户汇总列表。
+        按 last_active_time 降序排列。
+        数据库异常或无记录时返回空列表。
+        """
+        try:
+            with db_manager.get_session() as session:
+                results = session.query(
+                    ChatSession.tenant_id,
+                    func.count(ChatSession.id).label('session_count'),
+                    func.coalesce(func.sum(ChatSession.message_count), 0).label('message_count'),
+                    func.sum(
+                        case(
+                            (ChatSession.status == 'active', 1),
+                            else_=0
+                        )
+                    ).label('active_session_count'),
+                    func.max(ChatSession.updated_at).label('last_active_time')
+                ).group_by(
+                    ChatSession.tenant_id
+                ).order_by(
+                    desc('last_active_time')
+                ).all()
+
+                summary = []
+                for row in results:
+                    summary.append({
+                        'tenant_id': row.tenant_id,
+                        'session_count': row.session_count,
+                        'message_count': int(row.message_count),
+                        'active_session_count': int(row.active_session_count),
+                        'last_active_time': row.last_active_time.isoformat() if row.last_active_time else None
+                    })
+
+                return summary
+
+        except Exception as e:
+            logger.error(f"获取租户汇总失败: {e}")
+            return []
+
     # ==================== 会话管理方法 ====================
 
     def get_sessions_paginated(
@@ -726,13 +772,17 @@ class ConversationHistoryManager:
         per_page: int = 20,
         status: Optional[str] = None,
         search: str = '',
-        date_filter: str = ''
+        date_filter: str = '',
+        tenant_id: Optional[str] = None
     ) -> Dict[str, Any]:
         """分页获取会话列表"""
         try:
             with db_manager.get_session() as session:
                 query = session.query(ChatSession)
 
+                if tenant_id is not None:
+                    query = query.filter(ChatSession.tenant_id == tenant_id)
+
                 if status:
                     query = query.filter(ChatSession.status == status)