feat(layers): port BitmapLayer to WebGPU

[ibgreen-openai]

For #9504

Split from #10450.

Goal

Port the small, self-contained BitmapLayer rendering path to WebGPU and expose the website examples it directly unlocks.

Why this is low risk

• WebGL keeps the same GLSL shaders, shader-module list, and getBufferLayouts() call as master.
• The WGSL source and color module are selected only when device.type === 'webgpu'.
• The only WebGPU-specific layout adjustment removes the index buffer from vertex-buffer layouts because WebGPU binds index buffers separately.
• No shared core, aggregation, extension, or public API changes are included.

Website examples

Example	Layer/feature	Notes
TileLayer (Geospatial)	BitmapLayer sublayers	Raster OSM tiles render in WebGPU.
WMSLayer	BitmapLayer sublayer	WMS raster imagery renders in WebGPU.

Changes

• Add BitmapLayer WGSL for projection, coordinate conversion, texture sampling, tint/desaturation, opacity, and picking UV encoding.
• Add WGSL uniform and texture bindings while retaining the existing GLSL uniform blocks.
• Pass the selected device through the TileLayer and WMS website demos and enable their device tabs.

Validation

• yarn build
• yarn lint (passes; existing repository warnings remain)
• yarn test-headless test/modules/layers/bitmap-layer.spec.ts
• yarn test-website
• Manual Chrome runtime check: fresh WebGPU loads of /examples/tile-layer and /examples/wms-layer produced no BitmapLayer, shader, or pipeline console errors.

[coveralls]

coverage: 83.368% (-0.004%) from 83.372% — codex/webgpu-bitmap-layer into master

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: ab64ce1f15

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[ibgreen-openai]

Review follow-up: all reviewer threads are addressed and resolved in ffc254f. Local build, lint, focused BitmapLayer tests, and website checks passed. GitHub reports the PR approved and mergeable. CI finished with test-website and test-python green; test-node is blocked only by an unrelated MapboxOverlay timing failure in test/modules/mapbox/mapbox-overlay.spec.ts, where drawLog was [poi, poi] instead of [poi]. Rerun that check before merge.