Retry failed extractions on unpause, fix delete callback deps

- triggerPendingExtractions() now runs when unpausing, so packages
  with extraction errors are automatically retried
- executeDeleteSelection no longer depends on snapshot objects
  (prevents unnecessary re-renders with large queues)

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

src/main/download-manager.ts

@@ -2484,6 +2484,9 @@ export class DownloadManager extends EventEmitter {
           active.abortController.abort("stall");
         }
       }
+
+      // Retry failed extractions after unpause
+      this.triggerPendingExtractions();
     }
 
     this.persistSoon();