Any time warping will cause wrong chart offset

**Describe the bug**
When using Practice mode, despite the chart playback speed and song pitch being scaled by a user-defined factor, apparently there is a major desync between song and chart.

**To Reproduce**
Steps to reproduce the behavior:
1. Start any chart.
2. Enter practice mode mid-game.
3. Set any start pos & end pos & playback rate < 1.
4. Playback by pressing the top-left button.

**Expected behavior**
Synced playback of both song and chart.

**Screenshots**

https://github.com/user-attachments/assets/a67409ec-9666-4e40-914e-bef79d0761fd

**Device specs**
- Device: iQOO Neo 8
- OS: Android 14
- Version 2.0.0 Beta 2 Patch 5

I strongly appreciate the efforts that the developers put into making this mode possible. It's an incredible feature that few rhythm games (and emulators for them) are able to implement and make it a breeze for the users to use. Great job! 👍🏻

The issue is in practice mode's time-warping logic for syncing chart playback with audio. Look at the practice mode implementation, likely in a class handling playback speed and chart offset. Start by finding where playback rate is applied and how chart timing is adjusted. Check for any existing tests related to practice mode sync. 'Done' means the chart and song remain in sync at any playback rate in practice mode.

Written by the indexing model from the issue text.