fix(admin): name records by translatable (mltext) fields

The record heading, breadcrumb crumb and document title took the first
plain text field only, so records named by an mltext field fell back to
the generic update message. A shared recordDisplayName helper now takes
the first text or ML field and reads its default locale, then the first
non-empty one.

admin/tests/form/PreviewView.test.ts

@@ -4,6 +4,7 @@
 import { afterEach, beforeEach, describe, expect, it } from 'vitest'
 import { enableAutoUnmount, flushPromises, type VueWrapper } from '@vue/test-utils'
 import { setBundle } from '../../src/app/i18n'
+import { recordCrumb } from '../../src/state/useBreadcrumbs'
 import { toasts } from '../../src/state/useToasts'
 import PreviewView from '../../src/views/PreviewView.vue'
 import { clone, langFixture, rosterFormSchemaFixture, rosterRecordFixture } from '../fixtures/typed'
@@ -121,6 +122,23 @@ describe('preview view (UI-SPEC S3, D-11)', () => {
     expect(editor.findAll('[role="radiogroup"]').every((group) => group.attributes('aria-disabled') === 'true')).toBe(true)
   })
 
+  it('heads the record by the default locale of an mltext first field, and publishes it as the crumb', async () => {
+    const { wrapper } = await mountApp(
+      PREVIEW,
+      routes({
+        [`GET ${LIST}/schema/form`]: schemaWith((schema) => {
+          schema.meta.enabledLocales = ['en', 'pl']
+          schema.fields.find((field) => field.name === 'name')!.type = 'mltext'
+        }),
+        [`GET ${RECORD}`]: recordWith((record) => {
+          record.data.name = { en: 'Ada Lovelace', pl: 'Ada Lovelace PL' }
+        }),
+      }),
+    )
+    expect(wrapper.find('h1').text()).toBe('Ada Lovelace')
+    expect(recordCrumb.value).toBe('Ada Lovelace')
+  })
+
   it('shows the muted dash for an empty value and the label of a relation, never its id', async () => {
     const { wrapper } = await mountApp(PREVIEW, routes({ [`GET ${RECORD}`]: recordWith((record) => (record.data.joined_ip = null)) }))
     expect(wrapper.find('[data-preview-field="joined_ip"] [data-empty]').text()).toBe('—')