First-person hand and held item turn black when Y >= 2047

What I expected to happen: The player's first-person hand and held item should render normally with correct lighting, even at extremely high altitudes.

What actually happened: When the player flies to Y coordinate 2047 or higher, the first-person hand and held item turn completely black, indicating that the lighting engine fails to calculate light levels at this height (likely due to the 12-bit Y-coordinate limit overflow in the lighting system).

Steps to Reproduce:

1. Launch Minecraft in version 26.4 shapshot 8 without any mods.

2. Create a new world or load an existing one.

3. Switch to Creative mode and start flying upwards.

4. Continue flying until the Y coordinate reaches 2047 or higher.

5. Look at your first-person hand or held item.

Additional Information: This seems to be a boundary issue related to the lighting engine's Y-coordinate limits, similar to the historical MC-81067 but occurring at the 12-bit integer limit (2047). Please see the attached screenshot/video for evidence.