As mentioned in https://github.com/microsoft/terminal/issues/9354#issuecomment-790034728
`GETSET_SETTING` is too visually similar to `GETSET_PROPERTY`, but with a _VERY_ different meaning. I think that merely changing the name of the macro would make it harder for us to make this mistake again.
1. Fix progress value not updated
2. Introduce TabStatus object and bind both TabHeaderControl and CommandPalette to it
3. Add support for read-only mode indicator