Reorganize project structure for clarity

- Rename tests/wasm-app/ to tests/apps/ for brevity
- Move lib/gl_immediate_shim.js to wasm/shims/ (consolidates WASM files)
- Delete docs/ directory (outdated Nov 2024 research docs)
- Delete patches/ directory (already applied to fork submodules)
- Delete wasm/patches/ and wasm/config/ (empty/unused)
- Update all file references in scripts, configs, and documentation
- Update .gitignore for new tests/apps/ paths

Verified both build workflows pass:
- wxWidgets tests: 255 passed
- Docker KiCad build: completed successfully

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

tests/GL_README.md

@@ -107,4 +107,4 @@ All immediate mode tests pass with the color-per-vertex pattern:
 - Cyan line strip
 - Magenta line loop
 
-See `wasm-app/minimal_test.cpp` for working examples.
+See `apps/minimal_test.cpp` for working examples.