fix: keep release lockfile version aligned

[itzptk]

Summary

• Updates the release version bump script to keep package-lock.json root versions aligned with package.json.
• Treats either package.json or package-lock.json changes as release bump changes for --github-output.
• Stages package-lock.json alongside package.json in the stable release finalization commit.
• Adds a regression test that runs the release bump script against a temp fixture with a lockfile.

Closes #37

Verification

• RED before fix: npm run test:node -- release-versioning failed with expected '1.2.2' to be '1.2.3' for packageLock.version.
• npm ci passed.
• npm run test:node -- release-versioning passed: 1 file, 2 tests.
• npm run test:all passed: Angular tests 114 files / 252 tests, node tests 15 files / 117 tests. Note: local npm install scripts were blocked by the environment, so I manually extracted the cached Electron binary before the final full test run.
• npm run build passed: Angular production build and tsup Electron build succeeded.