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/lib/pwa.ts

@@ -18,7 +18,7 @@ export function registerServiceWorker() {
           newWorker.addEventListener('statechange', () => {
             if (newWorker.state === 'installed' && navigator.serviceWorker.controller) {
               // New content available, prompt user to refresh
-              showUpdatePrompt();
+              window.dispatchEvent(new CustomEvent('sw-update-available'));
             }
           });
         }
@@ -31,101 +31,27 @@ export function registerServiceWorker() {
   });
 }
 
-function showUpdatePrompt() {
-  // Dispatch custom event for UI to handle update prompt
-  const event = new CustomEvent('sw-update-available');
-  window.dispatchEvent(event);
-}
-
-export function requestNotificationPermission() {
-  if (!('Notification' in window) || !('serviceWorker' in navigator)) {
-    return Promise.resolve(false);
-  }
-
-  return Notification.requestPermission();
-}
-
-export async function subscribeToPush(registration: ServiceWorkerRegistration) {
-  if (!('PushManager' in window)) {
-    return null;
-  }
-
-  try {
-    const subscription = await registration.pushManager.subscribe({
-      userVisibleOnly: true,
-      applicationServerKey: urlBase64ToUint8Array(
-        process.env.NEXT_PUBLIC_VAPID_PUBLIC_KEY || ''
-      ),
-    });
-
-    console.log('Push subscription:', subscription);
-    return subscription;
-  } catch (error) {
-    console.error('Push subscription failed:', error);
-    return null;
-  }
-}
-
-function urlBase64ToUint8Array(base64String: string): Uint8Array {
-  const padding = '='.repeat((4 - (base64String.length % 4)) % 4);
-  const base64 = (base64String + padding).replace(/-/g, '+').replace(/_/g, '/');
-  const rawData = window.atob(base64);
-  const outputArray = new Uint8Array(rawData.length);
-
-  for (let i = 0; i < rawData.length; ++i) {
-    outputArray[i] = rawData.charCodeAt(i);
-  }
-
-  return outputArray;
+export async function subscribeToPush(_registration: ServiceWorkerRegistration) {
+  // Push subscription disabled for now - requires VAPID key setup
+  return null;
 }
 
 // Check if app is installed (PWA)
 export function isPWAInstalled(): boolean {
+  if (typeof window === 'undefined') return false;
   return (
     window.matchMedia('(display-mode: standalone)').matches ||
     (window.navigator as { standalone?: boolean }).standalone === true
   );
 }
 
-// Get install prompt
-export function getInstallPrompt(): { prompt: () => void; outcome: Promise<'accepted' | 'dismissed' | 'canceled'> } | null {
-  if (!('beforeinstallprompt' in window)) {
-    return null;
-  }
-
-  let deferredPrompt: beforeinstallpromptEvent | null = null;
-
-  window.addEventListener('beforeinstallprompt', (event) => {
-    event.preventDefault();
-    deferredPrompt = event;
-  });
-
-  return {
-    prompt: () => {
-      if (deferredPrompt) {
-        deferredPrompt.prompt();
-      }
-    },
-    outcome: new Promise((resolve) => {
-      if (deferredPrompt) {
-        deferredPrompt.userChoice.then((choiceResult) => {
-          deferredPrompt = null;
-          resolve(choiceResult.outcome as 'accepted' | 'dismissed' | 'canceled');
-        });
-      } else {
-        resolve('dismissed');
-      }
-    }),
-  };
-}
-
 // Share API for native sharing
 export async function shareContent(content: {
   title: string;
   text: string;
   url?: string;
 }): Promise<boolean> {
-  if (!navigator.share) {
+  if (typeof window === 'undefined' || !navigator.share) {
     return false;
   }