fix: v2.9.11 — Round 8 R8A engine math fix wave + cp_validator hardening #23

	name: crossval

	# Cross-validation runs the JS engine against a Python reference implementation.
	# The Python sibling lives in the CPP _cpp_common skills suite (not yet
	# open-source). This workflow verifies the test harness mechanically; the
	# Python reference must be supplied as a workflow secret or skipped.

	on:
	push:
	branches: [main, master]
	pull_request:
	branches: [main, master]
	workflow_dispatch:

	jobs:
	crossval:
	name: JS-Python crossval
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4

	- uses: actions/setup-node@v4
	with:
	node-version: '20'

	- uses: actions/setup-python@v5
	with:
	python-version: '3.11'

	- name: Check for Python reference
	id: check_ref
	shell: bash
	run: \|
	if [ -f "python_reference/cpm.py" ]; then
	echo "available=true" >> "$GITHUB_OUTPUT"
	else
	echo "available=false" >> "$GITHUB_OUTPUT"
	echo "::warning::Python reference (python_reference/cpm.py) not present in this repo."
	echo "::warning::Crossval will be skipped. Provide the reference to enable bit-identical parity checks."
	fi

	- name: Run crossval
	if: steps.check_ref.outputs.available == 'true'
	run: node cpm-engine.crossval.js

	- name: Verify engine version sync
	shell: bash
	run: \|
	PKG_VER=$(node -p "require('./package.json').version")
	ENGINE_VER=$(node -p "require('./cpm-engine.js').ENGINE_VERSION")
	if [ "$PKG_VER" != "$ENGINE_VER" ]; then
	echo "::error::Version skew detected. package.json=$PKG_VER engine=$ENGINE_VER"
	exit 1
	fi
	echo "Versions agree: v$PKG_VER"

Provide feedback