add ai descriptions and extracted text

src/lib/app-settings.ts

@@ -57,3 +57,11 @@ export function updateAiConfig(endpoint: string, model: string, enabled: boolean
   setSetting('ai_model', model)
   setSetting('ai_enabled', enabled ? 'true' : 'false')
 }
+
+export function getPreferredLanguage(): string {
+  return getSetting('preferred_language') ?? 'English'
+}
+
+export function setPreferredLanguage(language: string): void {
+  setSetting('preferred_language', language)
+}