Fix library repair failing on playback session foreign keys.

Delete stale playback sessions before removing unavailable or duplicate media file rows.

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

apps/master-api/src/metadata/service.ts

@@ -910,11 +910,7 @@ export class MetadataService {
     const seriesMerged = await this.mergeAllDuplicateSeries();
 
     // Unavailable rows left after the /media/movies → /mnt/user migration
-    const staleFilesRemoved = (
-      await prisma.mediaFile.deleteMany({
-        where: { available: false },
-      })
-    ).count;
+    const staleFilesRemoved = await this.deleteUnavailableMediaFiles();
 
     const duplicateFilesRemoved = await this.removeDuplicateMediaFiles();
 
@@ -1135,8 +1131,29 @@ export class MetadataService {
     }
 
     if (toDelete.length === 0) return 0;
-    const result = await prisma.mediaFile.deleteMany({ where: { id: { in: toDelete } } });
-    return result.count;
+    return this.deleteMediaFilesSafely(toDelete);
+  }
+
+  /** Remove playback sessions first — FK blocks direct media_file deletes. */
+  private async deleteMediaFilesSafely(ids: string[]): Promise<number> {
+    if (ids.length === 0) return 0;
+    const chunkSize = 500;
+    let deleted = 0;
+    for (let i = 0; i < ids.length; i += chunkSize) {
+      const chunk = ids.slice(i, i + chunkSize);
+      await prisma.playbackSession.deleteMany({ where: { mediaFileId: { in: chunk } } });
+      const result = await prisma.mediaFile.deleteMany({ where: { id: { in: chunk } } });
+      deleted += result.count;
+    }
+    return deleted;
+  }
+
+  private async deleteUnavailableMediaFiles(): Promise<number> {
+    const stale = await prisma.mediaFile.findMany({
+      where: { available: false },
+      select: { id: true },
+    });
+    return this.deleteMediaFilesSafely(stale.map((f) => f.id));
   }
 
   /** Admin: search TMDB by title (or resolve a single IMDb id). */