Use compileall for recursive compile checks

Stop letting the explicit compile step overstate its coverage. The old py_compile globs only touched top-level modules, so syntax errors in nested packages could slip past make check and release-check.\n\nAdd a shared compile-check recipe in Makefile that runs python -m compileall -q src tests, and have both check and release-check use it so the local verification paths stay aligned. Update the GitHub Actions compile step and the matching runtime validation evidence doc to describe the same recursive compile contract.\n\nValidate with python3 -m compileall -q src tests, make check, and make release-check.

.github/workflows/ci.yml

@@ -40,7 +40,7 @@ jobs:
           uv sync --active --frozen
           echo "${GITHUB_WORKSPACE}/.venv/bin" >> "${GITHUB_PATH}"
       - name: Run compile check
-        run: python -m py_compile src/*.py tests/*.py
+        run: python -m compileall -q src tests
       - name: Run unit and package-logic test suite
         run: python -m unittest discover -s tests -p 'test_*.py'