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/src/components/shell/Breadcrumbs.vue

@@ -9,7 +9,7 @@ import { activeEntry, firstControllerPath } from '../../state/useNavigation'
 import { settingsEntry } from '../../state/useSettings'
 
 // Header breadcrumbs (design: Top header): plugin, controller and record
-// labels, e.g. "Płytarium › Albumy › Enigmatic". Parent crumbs are muted
+// labels, e.g. "Demo › Widgets › Blue widget". Parent crumbs are muted
 // links; the current crumb uses the text colour at 600 with
 // aria-current="page". Separators are 14px chevron-right icons.
 interface Crumb {