feat: comprehensive CMS improvements

- Fix DOMPurify SSR crash (use isomorphic-dompurify)
- Fix SanitizedHtml to sanitize by default
- Add auth guards to studio/catalog maintenance pages
- Add update/edit to vouchers CRUD
- Add update/edit to rare-values CRUD
- Add approve workflow to applications page
- Add edit form to guilds detail page
- Add SEO metadata to all public pages (21 pages)
- Fix mobile nav accessibility (focus trap, aria attributes)
- Fix missing labels and table accessibility
- Add dynamic imports for heavy client components (6 components)
- Fix silent error swallowing (40+ locations)
- Add content scheduling for articles (publishAt, status)
- Wire up 12 missing webhook notification triggers
- Add global search to admin panel
- Add bulk actions to admin users table
- Fix JSON formatting and a11y issues

src/app/(site)/layout.tsx

@@ -1,12 +1,22 @@
+import dynamic from "next/dynamic";
 import type { ReactNode } from "react";
 import MotionPageWrapper from "@/components/motion-page-wrapper";
 import { Navigation } from "@/components/navigation";
-import RadioPlayerGate from "@/components/public/radio-player-gate";
 import { SiteFooter } from "@/components/site-footer";
 import { SiteHeader } from "@/components/site-header";
 import { TopHeader } from "@/components/top-header";
 import { auth } from "@/lib/auth";
 
+const RadioPlayerGate = dynamic(
+	() => import("@/components/public/radio-player-gate"),
+	{
+		loading: () => (
+			<div className="animate-pulse bg-[var(--admin-surface)] rounded h-12" />
+		),
+		ssr: false,
+	},
+);
+
 /**
  * Public site chrome. Route group `(site)` keeps this off `/admin` and `/client`,
  * so housekeeping is never constrained by the public max-w-7xl grid.