feat: refactor play area into sidebar layout with buttplug, recordings, and leaderboard sub-pages

- Add /play sidebar layout (mobile nav + desktop sidebar) with SexyBackground
- Move buttplug device control to /play/buttplug with Empty component and scan button
- Move recordings from /me/recordings to /play/recordings
- Move leaderboard to /play/leaderboard; redirect /leaderboard → /play/leaderboard
- Redirect /me/recordings → /play/recordings and /play → /play/buttplug
- Remove recordings entry from /me sidebar nav
- Rename "SexyPlay" → "Play", swap bluetooth icon for rocket, remove subtitle
- Add play.nav i18n keys (play, recordings, leaderboard, back_to_site, back_mobile)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/frontend/src/routes/play/+layout.server.ts

@@ -0,0 +1,8 @@
+import { redirect } from "@sveltejs/kit";
+
+export async function load({ locals }) {
+  if (!locals.authStatus.authenticated) {
+    throw redirect(302, "/login");
+  }
+  return { authStatus: locals.authStatus };
+}