feat: complete launch & marketing layer

- Add marketing pages: blog, changelog, roadmap, waitlist, security, maintenance
- Add GDPR cookie consent banner with preference modal
- Add referral system with API routes for code generation/tracking
- Add waitlist API with referral support
- Add PWA support: manifest, service worker, install prompt
- Add onboarding flow with 6-step guided tour
- Add in-app notification center with bell dropdown
- Add admin launch checklist (32 items across 8 categories)
- Update landing page with trust badges
- Add Open Graph image and favicon
- Configure ESLint for PWA install patterns
- Add LAUNCH_CHECKLIST.md with go-to-market guide

Supabase migrations for:
- blog_posts and blog_categories tables
- waitlist_signups table
- roadmap_items table
- launch_checklist_items table

src/components/referral/ReferralSystem.tsx

@@ -14,22 +14,15 @@ interface ReferralCode {
   created_at: string;
 }
 
-interface ReferralStats {
-  total_referrals: number;
-  successful_conversions: number;
-  total_reward_value: number;
-}
-
 interface ReferralSystemProps {
   brandId: string;
   userId: string;
-  userEmail: string;
 }
 
-export function ReferralSystem({ brandId, userId, userEmail }: ReferralSystemProps) {
+export function ReferralSystem({ brandId, userId }: ReferralSystemProps) {
   const [isGenerating, setIsGenerating] = useState(false);
   const [shareModalOpen, setShareModalOpen] = useState(false);
-  const [selectedCode, setSelectedCode] = useState<ReferralCode | null>(null);
+  const [selectedCode] = useState<ReferralCode | null>(null);
 
   const generateCode = async () => {
     setIsGenerating(true);