Feat/romanian translation (#663)

* feat(i18n): Add Romanian translation

* feat(i18n): Update Romanian translation to lang file changes

* feat(i18n): Add new Romanian translation entries

* fix(i18n): add settings.languageRo to remaining locale bundles

Romanian was missing from the language picker labels when UI was not en/ro;
add endonym-style names per locale (de/fr/nl/nb/ru/es/zh) for consistency.

* fix(i18n): use Romanian autonym for settings.languageRo everywhere

Match existing language picker convention (e.g. languageDe is Deutsch in
every locale bundle). Replaces UI-language translations of Romanian.

src/i18n.ts

@@ -8,6 +8,7 @@ import { nbTranslation } from './locales/nb';
 import { ruTranslation } from './locales/ru';
 import { nlTranslation } from './locales/nl';
 import { esTranslation } from './locales/es';
+import { roTranslation } from './locales/ro';
 
 const savedLanguage = localStorage.getItem('psysonic_language') || 'en';
 
@@ -23,6 +24,7 @@ i18n
       zh: { translation: zhTranslation },
       nb: { translation: nbTranslation },
       ru: { translation: ruTranslation },
+      ro: { translation: roTranslation },
     },
     lng: savedLanguage,
     fallbackLng: 'en',