PhET-iO design requests for 1.3 version

[arouinfar]

@jbphet @kathy-phet and I reviewed the issues currently open in the states-of-matter repo. There are a few issues that won't be fixed in time for the 1.2.0 delivery deadline, but it would be good to follow-up with a maintenance release once they've been addressed.

• Atom on interaction screen no longer line up with atom on the graph #277
• Studio search is still not working as expected #345
  Blue Star properties that aren't related to anything #346 (This is an API breaking change, projectorModeCheckbox PhET-iO tree structure joist#654)

I think the consensus from today's PhET-iO meeting was that these would also be addressed in the maintenance release.

• Radio button labels are not children of radio buttons #336
• In mirror inputs wrapper, top particles different from bottom particles #325

These are potential candidates for inclusion in a maintenance release, but they are tagged for further discussion at PhET-iO meeting.

• Support setting a partial instead of total state #338 / https://github.com/phetsims/phet-io/issues/1697
• Studio clears tree selection when switching between "Featured" and "All" radio buttons #319 / https://github.com/phetsims/studio/issues/168

Other common code changes that KP has said would be good to include in a MR:

• https://github.com/phetsims/studio/issues/177

[jbphet]

I'm going to unassign this until my priorities for the next couple of months are clear. If this is a high priority in that time frame, I'll assign it back to myself.