修复图片展示错误

backend/internal/modules/listing/presenter.go

@@ -306,20 +306,34 @@ func centToYuan(value int64) float64 {
 func cleanScreenshotURLs(urls []string) []string {
 	cleaned := make([]string, 0, len(urls))
 	seen := make(map[string]struct{}, len(urls))
-	for _, url := range urls {
-		url = strings.TrimSpace(url)
-		if url == "" {
+	for _, fileURL := range urls {
+		fileURL = normalizeDefaultScreenshotURL(strings.TrimSpace(fileURL))
+		if fileURL == "" {
 			continue
 		}
-		if _, ok := seen[url]; ok {
+		if _, ok := seen[fileURL]; ok {
 			continue
 		}
-		seen[url] = struct{}{}
-		cleaned = append(cleaned, url)
+		seen[fileURL] = struct{}{}
+		cleaned = append(cleaned, fileURL)
 	}
 	return cleaned
 }
 
+// normalizeDefaultScreenshotURL 把历史默认图地址升级到当前版本，避免浏览器继续吃旧 SVG 缓存。
+func normalizeDefaultScreenshotURL(fileURL string) string {
+	if fileURL == "" {
+		return ""
+	}
+	switch {
+	case fileURL == "/api/listings/default-upload-screenshot",
+		strings.HasPrefix(fileURL, "/api/listings/default-upload-screenshot?"):
+		return defaultUploadScreenshot
+	default:
+		return fileURL
+	}
+}
+
 func firstScreenshotURL(urls []string) string {
 	if len(urls) == 0 {
 		return ""

backend/internal/modules/listing/service.go

@@ -47,7 +47,7 @@ const (
 	defaultFireLevelMin           = 38
 	defaultPublishCooldownMinutes = 5
 	maxExternalUploadItems        = 10
-	defaultUploadScreenshot       = "/api/listings/default-upload-screenshot"
+	defaultUploadScreenshot       = "/api/listings/default-upload-screenshot?v=webp1"
 )
 
 type PublishCooldownError struct {