Neue Branding-Page und Gäste-PWA reagiert nun auf Branding-Einstellungen vom event-admin. Implemented local Google Fonts pipeline and admin UI selects for branding and invites.

- Added fonts:sync-google command (uses GOOGLE_FONTS_API_KEY, generates /public/fonts/google files, manifest, CSS, cache flush) and
    exposed manifest via new GET /api/v1/tenant/fonts endpoint with fallbacks for existing local fonts.
  - Imported generated fonts CSS, added API client + font loader hook, and wired branding page font fields to searchable selects (with
    custom override) that auto-load selected fonts.
  - Invites layout editor now offers font selection per element with runtime font loading for previews/export alignment.
  - New tests cover font sync command and font manifest API.

  Tests run: php artisan test --filter=Fonts --testsuite=Feature.
  Note: repository already has other modified files (e.g., EventPublicController, SettingsStoreRequest, guest components, etc.); left
  untouched. Run php artisan fonts:sync-google after setting the API key to populate /public/fonts/google.

resources/js/guest/lib/color.ts

@@ -0,0 +1,50 @@
+export function hexToRgb(hex: string): { r: number; g: number; b: number } | null {
+  const normalized = hex.trim();
+  if (!/^#([0-9a-fA-F]{3}|[0-9a-fA-F]{6})$/.test(normalized)) {
+    return null;
+  }
+
+  let r: number;
+  let g: number;
+  let b: number;
+
+  if (normalized.length === 4) {
+    r = parseInt(normalized[1] + normalized[1], 16);
+    g = parseInt(normalized[2] + normalized[2], 16);
+    b = parseInt(normalized[3] + normalized[3], 16);
+  } else {
+    r = parseInt(normalized.slice(1, 3), 16);
+    g = parseInt(normalized.slice(3, 5), 16);
+    b = parseInt(normalized.slice(5, 7), 16);
+  }
+
+  return { r, g, b };
+}
+
+export function relativeLuminance(hex: string): number {
+  const rgb = hexToRgb(hex);
+  if (!rgb) {
+    return 0;
+  }
+
+  const normalize = (channel: number) => {
+    const c = channel / 255;
+    return c <= 0.03928 ? c / 12.92 : ((c + 0.055) / 1.055) ** 2.4;
+  };
+
+  const r = normalize(rgb.r);
+  const g = normalize(rgb.g);
+  const b = normalize(rgb.b);
+
+  return 0.2126 * r + 0.7152 * g + 0.0722 * b;
+}
+
+export function getContrastingTextColor(
+  backgroundHex: string,
+  lightColor = '#ffffff',
+  darkColor = '#0f172a',
+): string {
+  const luminance = relativeLuminance(backgroundHex);
+
+  return luminance > 0.5 ? darkColor : lightColor;
+}