test(10.1-04): bring the SPA extension point under Vitest

- WidgetField: skeleton and aria-busy, the 5000 ms whenDefined timeout,
  script failure, attributes only, fill-values and locale sync, one POST
  while busy, fill-key-only patching, danger toasts, unmount
- PartialHost and partialNodes: exhaustive tag, attribute and URL
  allowlist, depth and node caps, skeleton sizes, empty, failure,
  busy refetch and ?id= only with a record
- PartialField, ListToolbar, ListView, registry, formState, FormField and
  FormView: group labels, registered toolbar actions, header refetch
  rules, form context provision and asset loading

admin/tests/form/formState.test.ts

@@ -11,7 +11,7 @@ import {
   tabDomId,
   tabOf,
 } from '../../src/components/form/formState'
-import { formField, formSchemaFixture } from '../fixtures/typed'
+import { extensionFormSchemaFixture, formField, formSchemaFixture } from '../fixtures/typed'
 
 afterEach(() => {
   document.body.innerHTML = ''
@@ -50,6 +50,13 @@ describe('form state helpers', () => {
     expect(body).toEqual({ name: 'Blue', tags: [3], active: false })
   })
 
+  it('never sends widget or partial fields, even with a value under their name', () => {
+    const fields = [formField('name'), ...extensionFormSchemaFixture.data.fields.filter((field) => field.type === 'widget' || field.type === 'partial')]
+    expect(fields.map((field) => field.type)).toEqual(['text', 'widget', 'partial'])
+    expect(editablePayload(fields, { name: 'Blue', lookup: 'x', summary: { nodes: [] } })).toEqual({ name: 'Blue' })
+    expect(initialValues(fields.slice(1))).toEqual({})
+  })
+
   it('starts a new record from defaults, toggles off and empty multiple relations', () => {
     const fields = [
       { ...formField('name'), default: 'Unnamed' },