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.
Similar to #9262. This creates another data template specifically for
command palette items that open up more options. We leverage the
localization key from #9262 to apply help text to this template
automatically.
Using the data template approach, we now have no need for the
`HasNestedComandsVisibilityConverter`, so that set of files is now
deleted. The logic to detect nested commands was moved to the template
selector.
## Validation Steps Performed
Tested using NVDA.
Addresses #7908 better