fix: sync package-lock.json to 0.6.0 and document lockfile step in COM workflow

package.json has been at 0.6.0 since release, but package-lock.json stayed at
0.3.11 because `npm run version-packages` (changesets) does not regenerate the
lockfile. This left `npm ci` broken against the committed state.

Also adds step 4 (`npm install --package-lock-only`) to the COM workflow in
CLAUDE.md so future releases keep the lockfile in sync automatically.

Credit to @Matt2012 (#70) for catching the lockfile drift.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>