Fix assorted issues when reloading pages with morphing and the pagination system

This patches 2 problems in Turbo/idiomorph that are causing problems when reloading the pagination frames:

- No remove callback in idiomorph when removing a node that had been mapped.
- Regression introduced by https://github.com/hotwired/turbo/pull/1311, where it won't prevent the removal of frames with refresh=morph

I will upstream both patches, this is temporary.

https://fizzy.37signals.com/5986089/cards/2291

app/javascript/controllers/pagination_controller.js

@@ -90,7 +90,6 @@ export default class extends Controller {
   #replacePaginationLinkWithFrame(linkElement) {
     const turboFrame = this.#buildTurboFrameFor(linkElement)
     this.#insertTurboFrameAtPosition(linkElement, turboFrame)
-    linkElement.remove()
   }
 
   #buildTurboFrameFor(linkElement) {