fix: detect actual MIME type for save-logo extension instead of hardcoded png

src/actions/save-logo.ts

@@ -13,7 +13,8 @@ export async function saveLogo(formData: FormData): Promise<{ success: boolean;
     const file = formData.get("file") as File | null;
     if (!file) return { success: false, error: "No file provided" };
 
-    const ext = "png";
+    const mimeExt: Record<string, string> = { "image/png": "png", "image/gif": "gif", "image/jpeg": "jpg", "image/webp": "webp" };
+    const ext = mimeExt[file.type] ?? "png";
     const filename = `logo-${Date.now()}-${Math.random().toString(36).slice(2, 8)}.${ext}`;
     const dir = path.join(process.cwd(), MEDIA_DIR);
     const filePath = path.join(dir, filename);