Consider moving from `selectize.js` to `tom-select`

[gadenbuie]

https://tom-select.js.org/

Tom Select is a dynamic, framework agnostic, and lightweight (~16kb gzipped) <select> UI control. With autocomplete and native-feeling keyboard navigation, it's useful for tagging, contact lists, country selectors, and so on. Tom Select was forked from selectize.js with four main objectives: modernizing the code base, decoupling from jQuery, expanding functionality, and addressing issue backlogs.