chore(lotus): clear pre-existing lint/prettier debt ahead of the CI gate

`pnpm lint:eslint` and `pnpm prettier:check` were never run by fork CI (#5),
and lotus HEAD failed both: a missing return type in lotusDecorations, a
type-only import in lotusWidget, and formatting drift in lotusAudioInject,
lotusFocus, lotusWidget and .gitea/workflows/ci.yml. No behaviour change.
Both gates now pass clean so they can be turned on.

Refs #5

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPmy3tPq869XDW4njjVaKA

src/lotus/lotusDecorations.ts

@@ -84,7 +84,7 @@ export function startLotusDecorations(): () => void {
       emit();
     };
     w.lazyActions.on(LotusWidgetActions.Decorations, handler);
-    unregister = () =>
+    unregister = (): void =>
       w.lazyActions.off(LotusWidgetActions.Decorations, handler);
   }
   registrations += 1;