feat: add scoped theme builder system with per-route, per-module, and multi-site support

- Add theme_scopes and theme_scope_values database tables for scoped themes
- Implement theme resolver engine with inheritance: global > site > module > route
- Add module detection for 20+ routes (shop, guilds, radio, news, etc.)
- Create admin UI at /admin/theme-builder with scope tree and color editor
- Add ScopedThemeVars component for injecting scoped CSS via data-attributes
- Add ThemeScopeDetector client component for runtime module/route detection
- Add site-resolver for multi-site domain detection
- Add /api/themes/export endpoint (JSON, CSS, variables formats)
- Add /api/themes/export/embed.js for external integration widget
- Add server actions for full CRUD on scopes and theme values
- Add admin nav link and EN/NL translations

src/app/layout.tsx

@@ -8,7 +8,9 @@ import { getLocale, getMessages } from "next-intl/server";
 import type { ReactNode } from "react";
 import { Toaster } from "sonner";
 import { PwaRegister } from "@/components/pwa-register";
+import { ScopedThemeVars } from "@/components/scoped-theme-vars";
 import { SmoothScroll } from "@/components/smooth-scroll";
+import { ThemeScopeDetector } from "@/components/theme-scope-detector";
 import { ThemeVars } from "@/components/theme-vars";
 import { enforceSiteAccess } from "@/lib/access-guard";
 import { resolveHotelName } from "@/lib/hotel-name";
@@ -96,6 +98,8 @@ export default async function RootLayout({
 			>
 				<NextIntlClientProvider locale={locale} messages={messages}>
 					<ThemeVars nonce={nonce} />
+					<ScopedThemeVars nonce={nonce} />
+					<ThemeScopeDetector />
 					{children}
 					<PwaRegister />
 					<SmoothScroll />