plot missing selection menus

[tdhock]

there should be a selection menu but there is not, why? we should add a test case and fix.
https://tdhock.github.io/SN-demo/

Update 27 Oct 2025: this example is now working, probably since #224

[tdhock]

another simpler example is here https://animint-manual-en.netlify.app/ch06#html-table-layout

issue above is there is no "foo" selector menu.

[tdhock]

possibly related to #224 which fixes #216 and altered logic which determines default display of selection menus.
@suhaani-agarwal can you please investigate?

[tdhock]

documentation of expected behavior is here https://animint-manual-en.netlify.app/ch06/#selectize-option

By default, animint2 will render a selection menu for every selection variable, with two exceptions:

• data-driven selection variables that are defined using named clickSelects and showSelected variables.
• selection variables that have a lot of values (they are slow to render).

the aes(color=x) example above #228 (comment) does not qualify for one of these two exceptions, so it should display a selection menu which we could use to turn on /off "foo"