Tighten up the Select (and Select-ish) fieldtypes

[jasonvarga]

Fixes a bunch of stuff related to "select-ish" fieldtypes: select, radio, checkboxes, button_group. The ones that have options.

• When a field has a value that isn't in the options, the label is the value, instead of getting an error. Fixes Migrating v2 pages with false values for selects results in an error exception #4204
• When you have cast_booleans enabled, null can also have a label. (Even though it's not technically a boolean)
• Fixed how they're rendered in listings.
• When you're using booleans, and you have a false, you can use {{ field:label }} to get the label.
• Extract the common bits to traits.
• Add tests and extract them to traits.
• Fixes how they're rendered in listings

[FrittenKeeZ]

Won't true also cause issues when just checking if it's truthy?

[jasonvarga]

What issue are you seeing?

[FrittenKeeZ]

If you pass true into $value ? array_get($this->config('options'), $value, $value) : $value, you'll get the same type error

[jasonvarga]

Ah yeah I didn't notice since I was checking using PHP8 which doesn't show that error. I see it on 7.4. 👍

[FrittenKeeZ]

Really good work 👍