Show small stitch-frame thumbs when a video collection is expanded.

Co-authored-by: Cursor <cursoragent@cursor.com>

server/utils/ffmpeg.ts

@@ -89,6 +89,24 @@ export async function extractLastFrame(inputPath: string, outputPath: string) {
   throw new Error('Could not extract the last frame. The video looks incomplete — interrupting Comfy mid-encode usually causes this. Earlier saved parts are still in the library.')
 }
 
+export async function extractFirstFrame(inputPath: string, outputPath: string) {
+  if (!existsSync(inputPath)) {
+    throw new Error('Source video is missing')
+  }
+  await runFfmpeg([
+    '-y',
+    '-i', inputPath,
+    '-frames:v', '1',
+    '-update', '1',
+    '-an',
+    '-q:v', '4',
+    outputPath
+  ], 20000)
+  if (!existsSync(outputPath)) {
+    throw new Error('Could not extract the first frame')
+  }
+}
+
 export async function probeHasAudio(filePath: string) {
   try {
     const out = await runFfprobe([