Feature/git flags --add and --amend

[Banh-Canh]

Fixes #

Proposed Changes

1. Add --add and --amend git commit flags
2. Add nix build

Readiness Checklist

Author/Contributor

• Add entry to the CHANGELOG listing the change and linking to the corresponding issue (if appropriate)
• If documentation is needed for this change, has that been included in this pull request

Reviewing Maintainer

• Label as breaking if this is a large fundamental change
• Label as either automation, bug, documentation, enhancement, infrastructure, or performance

[muandane]

Hello looks good to me, i'll bump up the version in the default.nix and merge

[Banh-Canh]

Thanks and thanks for this little TUI, I took a liking to it :)