feat(quick-261016-nqk): ListExtendRecords and FormRecordTitle admin hooks (G-18.1-4)

pact.ListExtendRecords fills unstored fields of one list page before its
columns are read (WinterCMS listExtendRecords); such columns compile
unsortable and refuse sortable/searchable. pact.FormRecordTitle names a
record; the show, create and update responses send it as meta.title.

docs/backend/forms.md

@@ -279,6 +279,7 @@ messages:
 - The screen shows every field whose `context` allows `preview`. A field without a `context` shows on every screen; `context: preview` shows a field only here. Values are rendered as text; `widget` and `relation-manager` fields are not shown.
 - A field with `context: preview` is never written. A save asks only for the `create` or the `update` context, so such a field in a request body is dropped like any field hidden on that form.
 - `messages.preview` is the screen's subtitle and `messages.edit` the label of its edit button; both default to framework texts (`cabana.FormMessages`).
+- The heading of the preview and of the update form is the record's name: the value of the form's first `text` (or multilingual text) field. A controller that implements `pact.FormRecordTitle` names the record itself, for example "Subscription #12 (Pro)": the show, create and update responses then carry its answer as `meta.title` (`cabana.RecordMeta`), which the SPA shows instead. The hook gets the loaded record and the request's database handle; an error fails the request.
 - `recordUrl` in `config_list.yaml` and the form's `create.redirect`, `update.redirectClose` and the other redirects may point at the screen as `<vendor>/<plugin>/<controller>/preview/:id`. On the update form of a record with a preview, the back arrow and Cancel return to the preview; after a delete the form goes to the list.
 - The footer holds the record actions the show response offers in `meta.actions`, then the edit button. After an action the record and the status hint are loaded again in place.