Adds docs/features/hoist-cpp-catches-simplification/ (diagnosis + Layer 1 result) and bumps the binaryen submodule to 1d40cf5a8 (FindAll/BranchUtils refactor + describe-as-is comments of HoistCppCatches). Validated end-to-end: full pcbnew build through the refactored wasm-opt + Firefox pcbnew e2e 6/6.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
