fix: video/audio save-load roundtrip (3 compounding bugs)

- Use API response imageId instead of locally generated ID in
  saveVideoAndGetRef/saveAudioAndGetRef (filename mismatch)
- Read result.video/result.audio instead of result.data in
  loadMediaById (response field mismatch)
- Add audio extensions and MIME types to load-generation route
  so audio files can be found and served

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/app/api/load-generation/route.ts

@@ -4,11 +4,14 @@ import * as path from "path";
 import { logger } from "@/utils/logger";
 
 // Supported file extensions
-const SUPPORTED_EXTENSIONS = ['png', 'jpg', 'jpeg', 'webp', 'gif', 'mp4', 'webm', 'mov'];
+const SUPPORTED_EXTENSIONS = ['png', 'jpg', 'jpeg', 'webp', 'gif', 'mp4', 'webm', 'mov', 'mp3', 'wav', 'ogg', 'flac', 'aac'];
 
 // Video extensions
 const VIDEO_EXTENSIONS = ['mp4', 'webm', 'mov'];
 
+// Audio extensions
+const AUDIO_EXTENSIONS = ['mp3', 'wav', 'ogg', 'flac', 'aac'];
+
 // Extension to MIME type mapping
 const EXT_TO_MIME: Record<string, string> = {
   png: 'image/png',
@@ -19,6 +22,11 @@ const EXT_TO_MIME: Record<string, string> = {
   mp4: 'video/mp4',
   webm: 'video/webm',
   mov: 'video/quicktime',
+  mp3: 'audio/mpeg',
+  wav: 'audio/wav',
+  ogg: 'audio/ogg',
+  flac: 'audio/flac',
+  aac: 'audio/aac',
 };
 
 // POST: Load a generated image or video from the generations folder by ID
@@ -108,7 +116,8 @@ export async function POST(request: NextRequest) {
 
     // Determine content type
     const isVideo = VIDEO_EXTENSIONS.includes(foundExtension);
-    const contentType = isVideo ? 'video' : 'image';
+    const isAudio = AUDIO_EXTENSIONS.includes(foundExtension);
+    const contentType = isVideo ? 'video' : isAudio ? 'audio' : 'image';
 
     logger.info('file.load', 'Generation loaded successfully', {
       filePath,
@@ -125,6 +134,8 @@ export async function POST(request: NextRequest) {
 
     if (isVideo) {
       response.video = dataUrl;
+    } else if (isAudio) {
+      response.audio = dataUrl;
     } else {
       response.image = dataUrl;
     }

src/utils/mediaStorage.ts

@@ -627,8 +627,9 @@ async function saveVideoAndGetRef(
       throw new Error(`Failed to save video: ${result.error}`);
     }
 
-    savedMediaIds.set(hash, videoId);
-    return videoId;
+    const actualId = result.imageId || videoId;
+    savedMediaIds.set(hash, actualId);
+    return actualId;
   })();
 
   if (!existingId) {
@@ -693,8 +694,9 @@ async function saveAudioAndGetRef(
       throw new Error(`Failed to save audio: ${result.error}`);
     }
 
-    savedMediaIds.set(hash, audioId);
-    return audioId;
+    const actualId = result.imageId || audioId;
+    savedMediaIds.set(hash, actualId);
+    return actualId;
   })();
 
   if (!existingId) {
@@ -1054,7 +1056,9 @@ async function loadMediaById(
     return ""; // Return empty string to avoid breaking the workflow
   }
 
-  const mediaData = mediaType === "image" ? result.image : result.data;
+  const mediaData = mediaType === "image" ? result.image
+    : mediaType === "video" ? result.video
+    : result.audio;
   loadedMedia.set(mediaId, mediaData);
   return mediaData;
 }