Create a non-modal dialog

[jessegreenberg]

PhET needs a non-modal Dialog component. It has come up a lot over the years:

• https://github.com/phetsims/sun/issues/882
• https://github.com/phetsims/joist/issues/293
• https://github.com/phetsims/sun/issues/433
• https://github.com/phetsims/models-of-the-hydrogen-atom/issues/86
• mean-share-and-balance
• natural-selection

433 describes features that are important for non-modal dialogs.

This issue describes accessibility behaviors that are important for non-modal dialogs.

This has come up several times in the last few months so adding to the developer priorities board.

[AgustinVallejo]

It was discussed on Nov 18, 2024 that this should be prioritized. And if a future sim needs it, the priority should be even higher? There's also an idea to add a 'Deprecated' annotation in the following sims, which created a non-modal panel:

• Mean Share and Balance (MeanInfoPanel)

[jessegreenberg]

We discussed during meeting that adding @deprecated is a way to track cases where a custom solution is being used, so that this is not forgotten.

I added it to the above list of cases.

We voted on a priority for this task in the "Developer Priorities" board. But this will also be motivated by the next sim that needs this component.