Noticable delay when transferring from/to tracks with realtime effects.

### Bug description

If the User moves a clip from/to a track with many realtime effects, there will be a delay between those actions.

### Steps to reproduce

1. Launch AU4
2. Create 3 tracks
3. Add multiple effects to a track
4. Generate clips
5. Move clip from track with multiple effects to a different track and vice versa
6. Observe result

### Expected behavior

There should be no delay

### Actual behavior

There is a delay

### Audacity Version

Audacity 4.0 beta 3

### Operating system

OS independent

### Additional context

Related: https://github.com/audacity/audacity/issues/9041

Reproduce the delay in AU4 beta 3 using the listed steps: create tracks, add multiple effects, generate clips, and move clips between affected tracks. Trace the clip-transfer path and realtime-effect handling, then verify that moving clips produces no observable delay.

Written by the indexing model from the issue text.