Form prefix/suffix redesign in Claro

Rerolled for 10.1.x.

There's a regression to the bulk operations form with #165. The "Action" label should be displayed inline.

Fixed the build and regression bug. Attached interdiff for same. please review

The last submitted patch, 169: 3082672-169.patch, failed testing. View results →

Even as someone who put a ton of work into this a few years back, I'm not sure this should go in as-is due to the many ways that #prefix/#suffix is used. This is a very opinionated style, and is great for things like adding a currency symbol before a "cost" field or "https://sitename/" before a relative path field.

There are many valid uses for #prefix/#suffix beyond these field-decorating ones. Several are successfully addressed in this issue, but it also strongly suggests that many contrib and custom modules use #prefix/#suffix in ways that would be disrupted by this change to Claro. Perhaps the flexibility of #prefix/#suffix makes this kind of styling prohibitively complex, but that flexibility has also made it possible to introduce valuable functionality.

I do like these styles, though. My thought is to make them opt-in, perhaps via an additional render array property. This way, fields that benefit from them can do so, but we can avoid surprises like #166, #161, #142, #135, #125, #96 etc, etc.