Fix admin product image handling and clarify support phone settings.

src/utils/catalogImage.ts

@@ -1,6 +1,12 @@
 const MAX_EDGE = 960
 const JPEG_QUALITY = 0.82
 
+export function toCssBackgroundUrl(url: string): string {
+  const trimmed = url.trim()
+  if (!trimmed) return ''
+  return `url("${trimmed.replace(/"/g, '\\"')}")`
+}
+
 export async function fileToCatalogImage(file: File): Promise<string> {
   if (!file.type.startsWith('image/')) {
     throw new Error('فقط فایل تصویری مجاز است.')