fix: improvements for globe view mode polygon tesselation

[igorDykhta]

Some polygons are badly tesselated in Globe mode

[Copilot]

Pull request overview

This PR improves polygon fill rendering in Globe mode by generating and rendering a refined (subdivided) triangulation for polygon fills, preventing long fill-triangle edges from bulging off the sphere and spilling past polygon outlines.

Changes:

• Add @math.gl/polygon and use earcut to triangulate polygon rings, then refine triangles via midpoint subdivision for globe-safe fills.
• Extend Arrow/WKB binary conversion to attach a separate polygonsFill geometry for globe fills while keeping original polygons for outlines.
• Update GeoJsonLayer rendering in globe mode to use the refined fill mesh (with caching to keep data references stable) and optionally render outlines via a second layer.

Reviewed changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 5 comments.

File	Description
yarn.lock	Adds lockfile metadata for the new @math.gl/polygon dependency.
src/layers/package.json	Adds @math.gl/polygon as a direct dependency of the layers package.
src/layers/src/layer-utils.ts	Builds refined polygon-fill mesh (polygonsFill) during WKB→binary conversion using earcut + triangle subdivision.
src/layers/src/geojson-layer/geojson-layer.ts	In globe mode, renders fill from polygonsFill and outline from original polygons, with a WeakMap cache for stable data references.

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