Limit large gaussians

[slimbuck]

Followup to #7696.

Reintroduce the 1024 pixel size limit, otherwise high resolution screens will have larger gaussians than before.

[Copilot]

Pull Request Overview

This PR reintroduces a 1024 px cap on the Gaussian kernel size to prevent excessively large kernels on high-resolution displays.

• Clamps the viewport-based kernel dimension (vmin) to a maximum of 1024 px.
• Applies the same change in both WGSL and GLSL shader variants.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
src/scene/shader-lib/wgsl/chunks/gsplat/vert/gsplatCorner.js	Added min(1024.0, …) clamp to vmin.
src/scene/shader-lib/glsl/chunks/gsplat/vert/gsplatCorner.js	Added min(1024.0, …) clamp to vmin.

Comments suppressed due to low confidence (2)

src/scene/shader-lib/wgsl/chunks/gsplat/vert/gsplatCorner.js:49

• Update this comment to mention that vmin is also capped at 1024 px to reflect the new clamp behavior.

    // Use the smaller viewport dimension to limit the kernel size relative to the screen resolution.

src/scene/shader-lib/glsl/chunks/gsplat/vert/gsplatCorner.js:48

• The comment should be extended to note that vmin is capped at 1024 px, matching the updated implementation.

    // Use the smaller viewport dimension to limit the kernel size relative to the screen resolution.