Map freeze on startup on Android Chrome & System WebView

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### mapbox-gl-js version

v3.21.0

### Browser and version

Android Chrome 146.0.7680.177 - Pixel 7 Pro (Android 16). The map is normally hosted in a Capacitor 8 app and uses Angular/zone.js.

### Expected behavior

Map starts up with the same performance it had on v3.20.0

### Actual behavior

After upgrading to 3.21.0, the map freezes on initial load on mobile. The same page loads in under 2 seconds on 3.20.0. This happens in both the device's Chrome browser and our Capacitor WebView.

I captured a Chrome DevTools performance trace on device. Three massive animation frames (8.5s, 11.8s, 5.1s) during map load. The dominant costs are two runs of these:

setupDepthForOcclusion → setTerrainUniformValues → set: ~16.5s (total)
upload: ~8.6s (total)

### Link to the demonstration

_No response_

### Steps to trigger the unexpected behavior

This seems to happen running a previously stable map component on Android Chrome as well as Android System WebView in a capacitor app.

I can share the specific map style privately to help debug. I've tested with 2 of our styles and had the same result.

### Relevant log output

```shell
Nothing came out in the logs
```

Reproduce the startup freeze on Android Chrome and Android System WebView with mapbox-gl-js v3.21.0, then compare it with v3.20.0. Start with the performance trace around setupDepthForOcclusion, setTerrainUniformValues, and upload; done means the map starts without the reported multi-second animation frames or regression.

Written by the indexing model from the issue text.