test(10-05): bring every SPA module, composable and component under Vitest

- 41 unit and component suites under admin/tests/{app,state,shell,list,form,relation,views,ui}
  covering states and a11y roles; every src module is imported by a test
- typed fixture helper assigns each JSON fixture to its generated OpenAPI type
- fix: iconFor ignores inherited object members such as "constructor"
- fix: field controls import ./control instead of the registry (import cycle
  left a renderer unregistered depending on module load order)
- fix: dropdown shows the placeholder for an unknown stored value next to an emptyOption
- fix: list announces a failed schema load even when the rows arrive after it
- tailwind no longer scans admin/tests; boardwalk/dist rebuilt

admin/tests/app/theme.test.ts

@@ -0,0 +1,34 @@
+import { afterEach, describe, expect, it } from 'vitest'
+import { applyColorScheme, DARK_QUERY } from '../../src/app/theme'
+import { fakeMedia } from '../helpers'
+
+afterEach(() => {
+  document.documentElement.classList.remove('dark')
+})
+
+describe('applyColorScheme (A6: system preference only)', () => {
+  it('sets .dark from prefers-color-scheme and follows changes until unsubscribed', () => {
+    const media = fakeMedia({ [DARK_QUERY]: true })
+    const stop = applyColorScheme()
+    expect(document.documentElement.classList.contains('dark')).toBe(true)
+    expect(media.listeners(DARK_QUERY)).toBe(1)
+
+    media.change(DARK_QUERY, false)
+    expect(document.documentElement.classList.contains('dark')).toBe(false)
+    media.change(DARK_QUERY, true)
+    expect(document.documentElement.classList.contains('dark')).toBe(true)
+
+    stop()
+    expect(media.listeners(DARK_QUERY)).toBe(0)
+    media.change(DARK_QUERY, false)
+    expect(document.documentElement.classList.contains('dark')).toBe(true)
+  })
+
+  it('stays light without matchMedia', () => {
+    document.documentElement.classList.add('dark')
+    const win = { document } as unknown as Window
+    const stop = applyColorScheme(win)
+    expect(document.documentElement.classList.contains('dark')).toBe(false)
+    expect(stop()).toBeUndefined()
+  })
+})