chore: lots of i18n

tests/renderer/components/SettingsView.i18n.test.tsx

@@ -4,6 +4,7 @@ import { render, screen } from '@testing-library/react';
 import { SettingsView } from '../../../src/renderer/components/SettingsView/SettingsView';
 import { useAppStore } from '../../../src/renderer/store';
 import { I18nProvider, UI_LANGUAGE_STORAGE_KEY } from '../../../src/renderer/i18n';
+import { SUPPORTED_RENDER_LANGUAGES } from '../../../src/main/shared/i18n';
 
 describe('SettingsView i18n', () => {
   beforeEach(() => {
@@ -59,4 +60,17 @@ describe('SettingsView i18n', () => {
     expect(screen.getByText('Projektname')).toBeInTheDocument();
     expect(screen.getByText('Projekteinstellungen speichern')).toBeInTheDocument();
   });
+
+  it('shows only supported render languages in project language selector', async () => {
+    render(
+      <I18nProvider>
+        <SettingsView />
+      </I18nProvider>
+    );
+
+    const select = await screen.findByLabelText('Hauptsprache');
+    const options = Array.from((select as HTMLSelectElement).options).map((option) => option.value);
+
+    expect(options).toEqual(SUPPORTED_RENDER_LANGUAGES);
+  });
 });

tests/renderer/i18n.test.ts

@@ -33,13 +33,19 @@ describe('renderer i18n', () => {
     expect(resolveSupportedUiLanguage('')).toBe('en');
   });
 
-  it('returns translated text with english fallback', () => {
+  it('returns translated text for supported languages without per-key english fallback', () => {
     expect(translateUi('de', 'common.save')).toBe('Speichern');
     expect(translateUi('fr', 'common.cancel')).toBe('Annuler');
     expect(translateUi('de', 'settings.language.english')).toBe('Englisch');
     expect(translateUi('it', 'missing.key')).toBe('missing.key');
   });
 
+  it('falls back to english only when requested language is unsupported', () => {
+    const resolved = resolveSupportedUiLanguage('pt-BR');
+    expect(resolved).toBe('en');
+    expect(translateUi(resolved, 'common.save')).toBe('Save');
+  });
+
   it('uses system locale for ui language when no persisted choice exists', async () => {
     localStorage.removeItem(UI_LANGUAGE_STORAGE_KEY);
     (window.electronAPI.app as { getSystemLanguage?: () => Promise<string> }).getSystemLanguage = async () => 'de-DE';