Add complete test infrastructure for WebGL GAL visual regression testing:
- scripts/test-gal-regression.sh: Master script that builds both backends,
runs tests, and performs two-level comparison (native vs baseline,
webgl vs native)
- scripts/build-gal-webgl-test.sh: WASM build using Makefile with em++
- tests/gal-regression/wasm/: WebGL test harness (stub WEBGL_GAL)
- tests/e2e/gal-webgl.spec.ts: Playwright test for screenshot capture
Fix Homebrew Emscripten environment in scripts/common/env.sh:
- Set EMSDK_PYTHON for Python 3.10+ (em++ reads this, not $PYTHON)
- Add bundled LLVM to PATH (Emscripten needs its clang with WASM backend)
Verified: Native vs Baseline passes (28/28), WebGL generates blank
screenshots as expected (WEBGL_GAL implementation is Phase 2).
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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