test(12.2-05): SPA unit tests for the phase and the check-phase12.2 gate

- sessionKey, dateFormat, FileuploadField (protected thumbnails and
  keyboard reorder backstops), RelationChildModal, RelationPivotModal,
  RelationManager row actions and create-screen deferral, date and time
  list cells; typed deferred relation-schema and file-list fixtures
- scripts/check-phase12.2.sh: go, security (named tests, refuses missing
  or skipped), spa, openapi, dist, docs, hygiene and app stages, a
  detector self-test, one PASS or FAIL line per stage under --all

admin/tests/list/CellValue.test.ts

@@ -75,3 +75,28 @@ describe('cell value (D-12)', () => {
     expect(cell(toggle, null).find('[data-switch]').exists()).toBe(false)
   })
 })
+
+describe('date and time cells (Phase 12.2)', () => {
+  const date = { ...listColumn('created_at'), key: 'released_on', type: 'date' } as ListColumn
+  const time = { ...listColumn('created_at'), key: 'opens_at', type: 'time' } as ListColumn
+
+  it('shows a stored date as is, never shifted by a time zone', () => {
+    expect(cell(date, '2026-10-02').text()).toBe('2026-10-02')
+    expect(cell(date, '2026-01-01T00:00:00Z').text()).toBe('2026-01-01')
+    expect(cell(date, '2026-10-02').find('span.tabular-nums').exists()).toBe(true)
+  })
+
+  it('shows a stored time without its seconds', () => {
+    expect(cell(time, '14:30:15').text()).toBe('14:30')
+    expect(cell(time, '08:05').text()).toBe('08:05')
+    expect(cell(time, '14:30:15').find('span.tabular-nums').exists()).toBe(true)
+  })
+
+  it('renders an empty date or time as a muted dash', () => {
+    for (const column of [date, time]) {
+      for (const value of [null, undefined, '']) {
+        expect(cell(column, value).find('[data-empty]').text()).toBe('—')
+      }
+    }
+  })
+})