v3: allow users to edit dump thumbnail, fixed some linter errors in the frontend

src/components/FilePreview.tsx

@@ -148,12 +148,15 @@ export default function FilePreview(
   const fileUrl = `${API_URL}/api/files/${dump.id}?v=${dump.fileSize ?? 0}`;
   const mime = dump.fileMime ?? "";
   const isPlaying = current?.kind === "file" && current.fileUrl === fileUrl;
+  const thumbOverride = dump.thumbnailMime
+    ? `${API_URL}/api/thumbnails/${dump.id}`
+    : null;
 
   if (compact) {
     if (mime.startsWith("image/")) {
       return (
         <img
-          src={fileUrl}
+          src={thumbOverride ?? fileUrl}
           alt={dump.fileName}
           className="rich-content-compact-thumbnail"
           onError={(e) => {
@@ -194,10 +197,19 @@ export default function FilePreview(
             play({ kind: "file", fileUrl, mimeType: mime, title: dump.title });
           }}
         >
-          <span className="rich-content-compact-icon">{mimeIcon(mime)}</span>
+          {thumbOverride
+            ? <VideoThumb src={thumbOverride} fallback={mimeIcon(mime)} />
+            : (
+              <span className="rich-content-compact-icon">
+                {mimeIcon(mime)}
+              </span>
+            )}
         </button>
       );
     }
+    if (thumbOverride) {
+      return <VideoThumb src={thumbOverride} fallback={mimeIcon(mime)} />;
+    }
     return <span className="rich-content-compact-icon">{mimeIcon(mime)}</span>;
   }
 
@@ -225,6 +237,7 @@ export default function FilePreview(
         >
           <video
             src={fileUrl}
+            poster={thumbOverride ?? undefined}
             preload="none"
             className="file-preview-video-thumb"
             muted
@@ -235,7 +248,14 @@ export default function FilePreview(
         </button>
       );
     }
-    return <MediaPlayer src={fileUrl} kind="video" mime={mime} />;
+    return (
+      <MediaPlayer
+        src={fileUrl}
+        kind="video"
+        mime={mime}
+        poster={thumbOverride ?? undefined}
+      />
+    );
   }
 
   if (mime.startsWith("audio/")) {