Refactor Qiniu upload integration and remove legacy handlers

- Replaced common upload handler and service with Qiniu-specific implementations in main.go and route registration.
- Deleted outdated upload_handler.go and qiniu_service.go files to streamline the codebase.
- Updated route definitions to utilize the new Qiniu upload handler for improved file upload management.

internal/common/qiniu/handler/upload_handler.go

@@ -0,0 +1,50 @@
+package handler
+
+import (
+	"errors"
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+
+	qiniuservice "wx_service/internal/common/qiniu/service"
+	"wx_service/internal/middleware"
+	"wx_service/internal/model"
+)
+
+type UploadHandler struct {
+	qiniuService *qiniuservice.QiniuService
+}
+
+func NewUploadHandler(qiniuService *qiniuservice.QiniuService) *UploadHandler {
+	return &UploadHandler{qiniuService: qiniuService}
+}
+
+type qiniuTokenRequest struct {
+	// filename 用于保留文件后缀（可选），例如："a.png"、"video.mp4"
+	Filename string `json:"filename"`
+}
+
+// QiniuToken 返回七牛直传所需的 token/key/upload_url 等信息。
+// 建议放在鉴权后：用当前登录用户生成 key，避免前端写入任意路径。
+func (h *UploadHandler) QiniuToken(c *gin.Context) {
+	user, ok := middleware.CurrentUser(c)
+	if !ok {
+		c.JSON(http.StatusUnauthorized, model.Error(http.StatusUnauthorized, "未登录或登录已过期"))
+		return
+	}
+
+	var req qiniuTokenRequest
+	_ = c.ShouldBindJSON(&req) // filename 可选，解析失败也不影响生成 token
+
+	token, err := h.qiniuService.CreateUploadToken(user.MiniProgramID, user.ID, req.Filename)
+	if err != nil {
+		if errors.Is(err, qiniuservice.ErrQiniuNotConfigured) {
+			c.JSON(http.StatusServiceUnavailable, model.Error(http.StatusServiceUnavailable, "未配置七牛上传服务，请联系管理员"))
+			return
+		}
+		c.JSON(http.StatusInternalServerError, model.Error(http.StatusInternalServerError, "获取上传凭证失败，请稍后重试"))
+		return
+	}
+
+	c.JSON(http.StatusOK, model.Success(token))
+}