Generation progress bar is stuck at 0%, fully filled up, when generating on a new track

1. Generate a 1h chirp on a new track
2. Observe the progress dialog

<img width="1512" height="858" alt="Image" src="https://github.com/user-attachments/assets/c50d5f6b-4712-496d-9e38-eff475c4da8e" />