Add video download failure reporting feature

- Introduced a new API endpoint `POST /api/v1/video/remove_watermark/report_failure` for reporting download failures.
- Added a new database table `video_download_failures` to store details about failed downloads, including domain, URL, error message, and reporting metadata.
- Updated the video handler to process failure reports and save them to the database.
- Enhanced documentation to include details about the new reporting feature and its usage.

internal/remove_watermark/model/video_parse.go

@@ -50,3 +50,25 @@ func (VideoParseUnlock) TableName() string {
 func (VideoParseUnlock) TableComment() string {
 	return "短视频去水印-每日广告解锁"
 }
+
+type VideoDownloadFailure struct {
+	ID        uint           `gorm:"primarykey" json:"id"`
+	CreatedAt time.Time      `gorm:"comment:创建时间" json:"created_at"`
+	UpdatedAt time.Time      `gorm:"comment:更新时间" json:"updated_at"`
+	DeletedAt gorm.DeletedAt `gorm:"index;comment:删除时间" json:"-"`
+
+	Domain       string    `gorm:"size:255;index;comment:来源域名" json:"domain"`
+	FailedURL    string    `gorm:"size:1000;comment:下载失败的URL" json:"failed_url"`
+	ErrorMessage string    `gorm:"type:text;comment:失败原因" json:"error_message"`
+	ReportedAt   time.Time `gorm:"index;comment:失败发生时间" json:"reported_at"`
+	UserAgent    string    `gorm:"size:255;comment:上报端UA" json:"user_agent"`
+	ClientIP     string    `gorm:"size:64;comment:上报IP" json:"client_ip"`
+}
+
+func (VideoDownloadFailure) TableName() string {
+	return "video_download_failures"
+}
+
+func (VideoDownloadFailure) TableComment() string {
+	return "短视频去水印-下载失败上报"
+}