v2.0.0

What's changed

• Nested CLI groups: repo, dependabot, and environment with subcommands
• repo create visibility via --public / --private / --internal (default public)
• Parser extracted into parser.py; thinner main.py entrypoint
• uv development dependencies migrated to PEP 735 [dependency-groups]

Documentation

• CLI guide
• Authentication
• Configuration (settings.toml / .secrets.toml)
• Changelog and release process documented

See CHANGELOG.md for details.