To test locally, install @angular-devkit/schematics-cli globally and use the schematics command line tool. That tool acts the same as the generate command of the Angular CLI, but also has a debug mode.
Check the documentation with
schematics --helpnpm run testwill run the unit tests, using jest.
npm run buildCommits follow conventional commit rules. You can read about it here. Additionally to support you with the proper format you can use
npm run commit