MNT: add TyphosDisplaySwitcher to positioner_row.ui

[tangkong]

Description

Adds TyphosDisplaySwitcher to row positioner widget.

This only required changes to the .ui file, to my complete amazement. 👏

Motivation and Context

closes #580 in this case, but not the general one.

How Has This Been Tested?

Clicking through all the other templates available to me, and I never got stuck

Where Has This Been Documented?

This PR

[tangkong]

pip py3.9 failed once with the standard flood of QMenus, but passed on rerun... :/

[ZLLentz]

This is a good call
Since we added the title/notes row, there's definitely room for this now

[ZLLentz]

There is some oddity here with the (?) button- it doesn't seem to functional when these are subdevices. I'd expect to see e.g. the motor class docstring or the ophyd doc field. Otherwise everything here works as expected.

[ZLLentz]

Actually- it seems like only for the positioner row templates, the ? button is completely non-functional. There must be some code reason for this.

[ZLLentz]

Ah, so I think the code for the help button is defined only in the full title bar widget, not in this button. So we'd need to do a bit of a refactor to make the help button work as intended.

[tangkong]

Ah you're totally right. The help frame is created and added to TyphosDisplayTitle, which sets up the toggle functionality and webviewer.

In the interest of keeping this template compact, maybe we just show the docstring via tooltip and disable clicking for this template.

[tangkong]

Something like this?