Some symbols disappear in globe projection between zoom levels 5 and 6

Nobody has claimed this yet.

**mapbox-gl-js version**: 2.13.0

**browser**: Chrome 111

### Description
Symbols of these types:
1. Line labels
2. Point labels with variable anchors
3. Symbols with both `text-variable-anchor` and `icon-text-fit` set

are not rendered in globe projection between `GLOBE_ZOOM_THRESHOLD_MIN` and `GLOBE_ZOOM_THRESHOLD_MAX`.

### Steps to Trigger Behavior

1. Go to https://codepen.io/osvodef/pen/povExxg
2. Zoom in

### Link to Demonstration
https://codepen.io/osvodef/pen/povExxg

### Expected Behavior
All labels stay visible while crossing zoom levels 5–6

### Actual Behavior
3 labels disappear, 1 stays

### Additional info
I did a bit of detective work myself on this issue, hope this helps.

I tracked the bug down to symbol vertex shaders and `u_zoom_transition` uniform. Forcing its value to 0 makes the labels appear, but on wrong positions on the screen, as if no globe→mercator transition is happening.

In the shaders, I found this line that hides the labels when `u_zoom_transition > 0`:
```
#if defined(PROJECTED_POS_ON_VIEWPORT) && defined(PROJECTION_GLOBE_VIEW)
projection_transition_fade = 1.0 - step(EPSILON, u_zoom_transition);
#endif
```

However, just removing this line doesn’t fix the issue since the screen coordinates calculated by the shader are also wrong when `u_zoom_transition > 0`, usually putting the symbol completely off-screen.

The `projection_transition_fade` line suggests that this was done intentionally, however, I couldn’t find any relevant discussion in PRs/issues here so I decided to report it anyway.

Start with the linked CodePen reproduction and inspect the symbol vertex shaders around u_zoom_transition, GLOBE_ZOOM_THRESHOLD_MIN/MAX, and projection_transition_fade. Compare the globe-to-Mercator transition calculations for line labels, variable-anchor point labels, and symbols using text-variable-anchor with icon-text-fit. Done means all affected labels remain visible and correctly positioned while crossing zoom levels 5–6.

Written by the indexing model from the issue text.