refactor: unify kubernetes_ table prefix, merge CI/CD models, LLM session support

- Rename container_clusters → kubernetes_clusters, container_topology_layouts → kubernetes_topology_layouts
- LLM: add session_id to chat history for multi-turn conversation support
- CI/CD: add pipeline_id, deploy_type, artifact_url, k8s_cluster_id to AppRelease
- Cleanup: remove deprecated playbook handler, simplify automation models
- Database: optimize auto-migrate model list
- Frontend: AIOps assistant improvements, api.ts updates

backend/internal/api/handlers/llm_chat.go

@@ -90,9 +90,14 @@ func (h *LLMHandler) Chat(c *gin.Context) {
 		// 取最后一条用户消息（前端已附加当前提问）
 		lastUser := req.Messages[len(req.Messages)-1]
 		now := time.Now()
+		// session_id：前端传入或后端生成（兼容旧版客户端） // Logan.Li
+		sid := req.SessionID
+		if sid == "" {
+			sid = fmt.Sprintf("sess-%d", now.UnixMilli())
+		}
 		h.db.Create(&[]models.ChatHistory{
-			{UserID: uid, Role: "user", Content: lastUser.Content, CreatedAt: now},
-			{UserID: uid, Role: "assistant", Content: replyContent, Model: cfg.Model, CreatedAt: now.Add(time.Millisecond)},
+			{UserID: uid, SessionID: sid, Role: "user", Content: lastUser.Content, CreatedAt: now},
+			{UserID: uid, SessionID: sid, Role: "assistant", Content: replyContent, Model: cfg.Model, CreatedAt: now.Add(time.Millisecond)},
 		})
 	}
 
@@ -251,9 +256,14 @@ func (h *LLMHandler) ChatStream(c *gin.Context) {
 		if uid != 0 {
 			lastUser := req.Messages[len(req.Messages)-1]
 			now := time.Now()
+			// session_id：前端传入或后端生成（兼容旧版客户端） // Logan.Li
+			sid := req.SessionID
+			if sid == "" {
+				sid = fmt.Sprintf("sess-%d", now.UnixMilli())
+			}
 			h.db.Create(&[]models.ChatHistory{
-				{UserID: uid, Role: "user", Content: lastUser.Content, CreatedAt: now},
-				{UserID: uid, Role: "assistant", Content: fullContent, Model: cfg.Model, CreatedAt: now.Add(time.Millisecond)},
+				{UserID: uid, SessionID: sid, Role: "user", Content: lastUser.Content, CreatedAt: now},
+				{UserID: uid, SessionID: sid, Role: "assistant", Content: fullContent, Model: cfg.Model, CreatedAt: now.Add(time.Millisecond)},
 			})
 		}
 		// 发送结束标志