Remove sharp, jsdom, node-canvas

[slimbuck]

This PR:

• swap sharp for libwebp compiled to wasm
• add a stub for global window, document and canvas to replace jsdom and node-canvas

This results in no functionality change, but means we have a smaller dependency footprint resulting in (hopefully) fewer issues across the various platforms.

Also might help with bundling to binary.

[Copilot]

Pull Request Overview

This PR removes dependencies on sharp, jsdom, and node-canvas by replacing them with custom implementations to reduce the dependency footprint and improve cross-platform compatibility.

• Replaces sharp image processing with a custom WebP encoder compiled to WASM
• Replaces jsdom and node-canvas with minimal stubs for browser APIs
• Updates build configuration to exclude the removed dependencies

Reviewed Changes

Copilot reviewed 10 out of 14 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/writers/write-sog.ts	Replaces sharp WebP encoding with custom WebpEncoder and adds file writing utility
src/utils/webp.ts	Implements new WebpEncoder class using WASM-compiled libwebp
src/process.ts	Renames process function to processDataTable to avoid naming conflicts
src/index.ts	Updates imports to use renamed processDataTable function
src/gpu/gpu-device.ts	Replaces jsdom with minimal stubs for window, document, and canvas APIs
rollup.config.mjs	Removes sharp and jsdom from external dependencies
package.json	Removes canvas, jsdom, and sharp dependencies; adds lib/ to files
lib/webp_encode.mjs	Adds WASM-compiled WebP encoder module
lib/webp_encode.c	Adds C source code for WebP encoding functions
lib/BUILD.md	Adds build instructions for the WebP WASM module

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[willeastcott]

Very cool indeed!