feat: translations now use crowdin (translate.unraid.net) (#1739)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

- **New Features**
- App-wide internationalization: dynamic locale detection/loading, many
new locale bundles, and CLI helpers to extract/sort translation keys.

- **Accessibility**
  - Brand button supports keyboard activation (Enter/Space).

- **Documentation**
  - Internationalization guidance added to API and Web READMEs.

- **Refactor**
- UI updated to use centralized i18n keys and a unified locale loading
approach.

- **Tests**
  - Test utilities updated to support i18n and localized assertions.

- **Chores**
- Crowdin config and i18n scripts added; runtime locale exposed for
selection.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

web/__test__/store/server.test.ts

@@ -19,6 +19,14 @@ import type {
 
 import { WebguiState } from '~/composables/services/webgui';
 import { useServerStore } from '~/store/server';
+import { testTranslate } from '../utils/i18n';
+
+// Mock vue-i18n for store tests
+vi.mock('vue-i18n', () => ({
+  useI18n: () => ({
+    t: testTranslate,
+  }),
+}));
 
 type MockServerStore = ReturnType<typeof useServerStore> & Record<string, unknown>;