scripts/lib/npm-version-check-diagnosis.cjs (added earlier in this
branch) ships to every install (bin/install.js copies scripts/lib/
wholesale) but was missing from GSD_SCRIPTS_LIB_FILES, so uninstall()
would never remove it -- it would orphan on every uninstall. Confirmed
by gsd-test: tests/install.test.cjs's own parity check named the exact
missing filename and the array to add it to.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>