feat: 文件上传接口直接返回完整 URL + 提现 content 改为非必填

- FileUploadResponse / FileUploadCompleteResponse 精简为只返回 url
- S3Store.BuildObjectURL 拼接完整访问地址
- 提现 method=0 时 content 不再参与必填校验
- 新增用户端 API 接口文档

internal/logic/public/file/fileuploadlogic.go

@@ -52,20 +52,13 @@ func (l *FileUploadLogic) FileUpload(req *types.FileUploadRequest, fileHeader *m
 	fileID := buildFileID(u.Id, req.BizType, fileHeader.Filename)
 	objectKey := buildObjectKey(l.svcCtx.Config.S3.Prefix, u.Id, req.BizType, fileID, fileHeader.Filename, now)
 
-	putResult, err := l.svcCtx.S3Store.PutObject(l.ctx, objectKey, file, fileHeader.Size, contentType)
-	if err != nil {
+	if _, err := l.svcCtx.S3Store.PutObject(l.ctx, objectKey, file, fileHeader.Size, contentType); err != nil {
 		l.Errorw("put object failed", logger.Field("error", err.Error()), logger.Field("user_id", u.Id), logger.Field("file_id", fileID))
 		return nil, err
 	}
 
 	return &types.FileUploadResponse{
-		FileId:      fileID,
-		FileName:    fileHeader.Filename,
-		ObjectKey:   objectKey,
-		Size:        fileHeader.Size,
-		ContentType: contentType,
-		Etag:        putResult.ETag,
-		Status:      fileUploadCompleteStatus,
+		Url: l.svcCtx.S3Store.BuildObjectURL(objectKey),
 	}, nil
 }