Better tests, more tests, working tests

What's Changed

• Nix: re-enable package checks, fix tests & ci by @faukah in #75
• build(deps): bump actions/checkout from 6.0.2 to 6.0.3 by @dependabot[bot] in #76
• dix-diff: version: fix ordering transitivity by @faukah in #80
• version: derive Ord for ComponentRank by @amaanq in #81
• meta: tag v2.0.1 by @faukah in #79

New Contributors

• @amaanq made their first contribution in #81

Full Changelog: v2.0.0...v2.0.1