Merge pull request '失效图片预览保留下载按钮' (#33) from codex/image-preview-download-placeholder-20261104 into main

components/image-preview.tsx

@@ -307,9 +307,16 @@ export function ImagePreview({
           }}
           loading="lazy"
           decoding="async"
+          onLoad={(event) => {
+            event.currentTarget.style.aspectRatio = "";
+            event.currentTarget.alt = "Generated Image";
+          }}
           onError={(event) => {
             if (event.currentTarget.src !== (thumbnail || original)) {
               event.currentTarget.src = thumbnail || original;
+            } else if (!compactGrid) {
+              event.currentTarget.style.aspectRatio = "1";
+              event.currentTarget.alt = "预览暂不可用，可尝试下载原图";
             }
           }}
           onClick={() => setIsOpen(true)}