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_history.go

@@ -9,16 +9,24 @@ import (
 	"github.com/gin-gonic/gin"
 )
 
-// GetChatHistory 获取当前用户的对话历史（按时间正序，仅返回最近 100 条避免过大） // Logan.Li
-// GET /api/v1/aiops/chat-history
+// GetChatHistory 获取当前用户的对话历史（按 session_id 过滤，默认返回最新 session） // Logan.Li
+// GET /api/v1/aiops/chat-history?session_id=xxx
 func (h *LLMHandler) GetChatHistory(c *gin.Context) {
 	uid := middleware.GetUserID(c)
+	sid := c.Query("session_id")
 	var rows []models.ChatHistory
-	// 子查询取最近 100 条后再正序返回，保证前端渲染顺序正确 // Logan.Li
-	h.db.Where("user_id = ?", uid).
-		Order("id DESC").
-		Limit(100).
-		Find(&rows)
+	q := h.db.Where("user_id = ?", uid)
+	// 指定 session_id 直接过滤；未指定则查最新 session // Logan.Li
+	if sid != "" {
+		q = q.Where("session_id = ?", sid)
+	} else {
+		// 取该用户最新的 session_id（id 最大那条的 session_id）
+		var latest models.ChatHistory
+		if err := h.db.Where("user_id = ?", uid).Order("id DESC").First(&latest).Error; err == nil && latest.SessionID != "" {
+			q = q.Where("session_id = ?", latest.SessionID)
+		}
+	}
+	q.Order("id DESC").Limit(100).Find(&rows)
 	// 反转为时间正序（最早在前）
 	for i, j := 0, len(rows)-1; i < j; i, j = i+1, j-1 {
 		rows[i], rows[j] = rows[j], rows[i]