git: Fully implement "all staged" checkbox (#23079)

Also includes some improvements to the "stage/unstage all" actions and
buttons.

Release Notes:

- N/A

Cole Miller committed 1y ago

bd3c7d6cbffda730c0c2c7e468a1deecb61a3312

Parent: 2179be1

Committed by GitHub <noreply@github.com> on 1/13/2025, 8:13:14 PM