feat(dictation): add persistent language selection in General settings

components/settings-signal.ts

@@ -20,7 +20,7 @@ export const SETTINGS_SAVED_EVENT = "lh:settings-saved";
 // "keys" joined the roster (zero-keys wave, 2026-09-25): keys-section
 // dispatches it after save AND delete — deletions used to be invisible to
 // the zero-keys pill and the setup dialog's auto-advance.
-export type SettingsSection = "general" | "keys" | "agent" | "models" | "appearance" | "graph" | "compaction";
+export type SettingsSection = "general" | "keys" | "agent" | "models" | "appearance" | "graph" | "compaction" | "dictation";
 
 /** Writers call this after the PUT resolves ok — never before (a failed
  *  write notifies nothing; the record is unchanged). */
@@ -47,4 +47,4 @@ export function useSettingsSaved(handler: (section: SettingsSection) => void): v
 	const saved = useRef(handler);
 	saved.current = handler;
 	useEffect(() => onSettingsSaved((section) => saved.current(section)), []);
-}
+}