refactor: 将客服后端重构为宿主可嵌入模块

- 注入数据库、运行时配置、统一响应、文件存储和平台 AI 能力，补充业务读写工具与客户快捷操作契约。

- 移除模块内重复的组织、客户、工单、标签、技能、旧工作流、MCP 和迁移实现，将身份权限与业务主体交由宿主管理。

- 使用 libSQL 重构向量存储，并完善图片消息、访客身份、排队调度、企业微信和支持聊天页面。

- 统一 HTTP、DTO 与 WebSocket 的 snake_case 协议，补齐模块初始化、业务动作和公共载荷等回归测试。

internal/pkg/httpx/response.go

@@ -1,9 +1,11 @@
 package httpx
 
 import (
+	"code.tczkiot.com/wlw/ai-agent/contract"
 	"code.tczkiot.com/wlw/ai-agent/internal/pkg/errorsx"
 	"code.tczkiot.com/wlw/ai-agent/internal/pkg/i18nx"
 	"net/http"
+	"sync"
 
 	"github.com/gin-gonic/gin"
 	"github.com/mlogclub/simple/sqls"
@@ -21,10 +23,32 @@ type pageData struct {
 	paging  *sqls.Paging
 }
 
+type cursorResult struct {
+	Results any    `json:"results"`
+	Cursor  string `json:"cursor"`
+	HasMore bool   `json:"has_more"`
+}
+
+type pageResult struct {
+	Page    *sqls.Paging `json:"page"`
+	Results any          `json:"results"`
+}
+
 type localizedError interface {
 	Message(locale string) string
 }
 
+var (
+	responseWriterMu sync.RWMutex
+	responseWriter   contract.ResponseWriter
+)
+
+func SetResponseWriter(writer contract.ResponseWriter) {
+	responseWriterMu.Lock()
+	defer responseWriterMu.Unlock()
+	responseWriter = writer
+}
+
 func CursorData(results any, cursor string, hasMore bool) any {
 	return cursorData{results: results, cursor: cursor, hasMore: hasMore}
 }
@@ -34,11 +58,36 @@ func PageData(results any, paging *sqls.Paging) any {
 }
 
 func WriteJSON(ctx *gin.Context, result any) {
-	ctx.JSON(http.StatusOK, buildJSONResult(ctx, result))
+	writeJSON(ctx, http.StatusOK, result)
 }
 
 func WriteHttpStatusJSON(ctx *gin.Context, statusCode int, result any) {
-	ctx.JSON(statusCode, buildJSONResult(ctx, result))
+	writeJSON(ctx, statusCode, result)
+}
+
+func AbortJSON(ctx *gin.Context, statusCode int, result any) {
+	writeJSON(ctx, statusCode, result)
+	ctx.Abort()
+}
+
+func writeJSON(ctx *gin.Context, statusCode int, result any) {
+	payload := buildJSONResult(ctx, result)
+	responseWriterMu.RLock()
+	writer := responseWriter
+	responseWriterMu.RUnlock()
+	if writer == nil {
+		ctx.JSON(statusCode, payload)
+		return
+	}
+	if err := writer(ctx.Writer, ctx.Request, contract.Response{
+		StatusCode: statusCode,
+		ErrorCode:  payload.ErrorCode,
+		Message:    payload.Message,
+		Data:       payload.Data,
+		Success:    payload.Success,
+	}); err != nil {
+		_ = ctx.Error(err)
+	}
 }
 
 func buildJSONResult(ctx *gin.Context, result any) *web.JsonResult {
@@ -62,9 +111,24 @@ func buildJSONResult(ctx *gin.Context, result any) *web.JsonResult {
 	case error:
 		return web.JsonError(value)
 	case cursorData:
-		return web.JsonCursorData(value.results, value.cursor, value.hasMore)
+		results := value.results
+		if results == nil {
+			results = []any{}
+		}
+		return web.JsonData(&cursorResult{
+			Results: results,
+			Cursor:  value.cursor,
+			HasMore: value.hasMore,
+		})
 	case pageData:
-		return web.JsonPageData(value.results, value.paging)
+		results := value.results
+		if results == nil {
+			results = []any{}
+		}
+		return web.JsonData(&pageResult{
+			Page:    value.paging,
+			Results: results,
+		})
 	case web.RspBuilder:
 		return value.JsonResult()
 	case *web.RspBuilder: