feat(layers) Port SolidPolygonLayer to WebGPU

[ibgreen]

Partial WIP port of SolidPolygonLayer

extrusions are not working.

Summary

This PR ports SolidPolygonLayer to WGSL/WebGPU and updates the GeoJSON polygons example so it can be exercised from the website’s device tabs.

Changes

SolidPolygonLayer WebGPU support

• Added a WGSL shader implementation for SolidPolygonLayer.
• Wired SolidPolygonLayer to provide WGSL shader source on WebGPU while keeping the existing GLSL path for WebGL.
• Added WGSL uniform support for solidPolygon.
• Added WebGPU-specific model setup and buffer-layout filtering for top, side, and wireframe models.
• Updated picking color handling to work with the WebGPU path.

Core WebGPU plumbing fixes

• Updated core attribute/buffer handling to better support WebGPU requirements in this path.
• Adjusted lighting/shadow behavior so the example remains usable on WebGPU.
• Kept shared layer rendering behavior aligned with the existing WebGL path rather than introducing global WebGPU polygon-offset changes.

Example updates

• Enabled WebGL2/WebGPU device tabs for the GeoJSON polygons example.
• Updated the GeoJSON website app to pass through the selected device and use WebGPU-specific premultiplied-alpha blend parameters.
• Added the same device-tab support to the Globe and Trips examples.
• Updated the playground Vite config to support the example/dev workflow used during this port.

Files changed

• modules/layers/src/solid-polygon-layer/solid-polygon-layer.wgsl.ts
• modules/layers/src/solid-polygon-layer/solid-polygon-layer.ts
• modules/layers/src/solid-polygon-layer/solid-polygon-layer-uniforms.ts
• modules/core/src/lib/attribute/attribute.ts
• modules/core/src/lib/attribute/data-column.ts
• modules/core/src/lib/attribute/attribute-manager.ts
• modules/core/src/lib/layer.ts
• modules/core/src/effects/lighting/lighting-effect.ts
• examples/website/geojson/app.tsx
• website/src/examples/geojson-layer-polygons.js
• examples/website/globe/app.tsx
• website/src/examples/globe-view.js
• examples/website/trips/app.tsx
• website/src/examples/trips-layer.js
• examples/playground/vite.config.js

Validation

• ./node_modules/.bin/tsc -p modules/layers/tsconfig.json --noEmit
• ./node_modules/.bin/vitest run --project render test/render/test-cases/geojson-layer.spec.ts
• npm run build-bundle --prefix modules/layers

Notes

• Temporary debug screenshots were removed and are not part of the PR.
• The remaining follow-up issue is WebGPU polygon z-fighting / extrusion behavior in the live example, which needs a layer-local fix rather than a shared Layer draw-state change.