feat(pwa): adopt thread-ripper pattern with in-app install buttons, floating banner, and GET share_target

public/sw.js

@@ -1,18 +1,20 @@
-// Everclone PWA Service Worker (v1.1.0)
-const CACHE_NAME = 'everclone-cache-v2';
-const PRECACHE_URLS = [
+// Everclone PWA Service Worker (v2.0.0)
+const CACHE_NAME = 'everclone-cache-v3';
+const STATIC_ASSETS = [
   '/',
   '/manifest.json',
-  '/icon.svg',
   '/icon-192.png',
   '/icon-512.png',
-  '/apple-touch-icon.png'
+  '/icon-maskable-192.png',
+  '/icon-maskable-512.png',
+  '/apple-touch-icon.png',
+  '/icon.svg'
 ];
 
 self.addEventListener('install', (event) => {
   event.waitUntil(
     caches.open(CACHE_NAME).then((cache) => {
-      return cache.addAll(PRECACHE_URLS).catch(() => {});
+      return cache.addAll(STATIC_ASSETS).catch(() => {});
     })
   );
   self.skipWaiting();
@@ -31,44 +33,47 @@ self.addEventListener('activate', (event) => {
 
 self.addEventListener('fetch', (event) => {
   // CRITICAL: Never intercept POST/PUT/DELETE requests!
-  // This ensures Android Web Share Target multipart POSTs stream directly to /api/hooks/note
   if (event.request.method !== 'GET') {
     return;
   }
 
   const url = new URL(event.request.url);
 
-  // Bypass API endpoints, hooks, and share endpoint to always get fresh data
-  if (url.pathname.startsWith('/api/') || url.pathname === '/share') {
+  // Bypass API endpoints and share endpoint
+  if (url.pathname.startsWith('/api/') || url.pathname.startsWith('/share')) {
     return;
   }
 
-  // Network-first strategy for navigation and static assets with cache fallback
+  // For page navigations (including share target queries like /?url=... or /?noteId=...)
+  if (event.request.mode === 'navigate') {
+    event.respondWith(
+      fetch(event.request).catch(() => {
+        return caches.match('/');
+      })
+    );
+    return;
+  }
+
+  // Stale-while-revalidate for static assets
   event.respondWith(
-    fetch(event.request)
-      .then((networkResponse) => {
-        if (
-          networkResponse &&
-          networkResponse.status === 200 &&
-          (url.pathname === '/' || url.pathname.startsWith('/_next/static/'))
-        ) {
-          const responseClone = networkResponse.clone();
-          caches.open(CACHE_NAME).then((cache) => {
-            cache.put(event.request, responseClone);
-          });
-        }
-        return networkResponse;
-      })
-      .catch(() => {
-        return caches.match(event.request).then((cachedResponse) => {
-          if (cachedResponse) {
-            return cachedResponse;
+    caches.match(event.request).then((cachedResponse) => {
+      const fetchPromise = fetch(event.request)
+        .then((networkResponse) => {
+          if (
+            networkResponse &&
+            networkResponse.status === 200 &&
+            (url.pathname === '/' || url.pathname.startsWith('/_next/static/'))
+          ) {
+            const responseClone = networkResponse.clone();
+            caches.open(CACHE_NAME).then((cache) => {
+              cache.put(event.request, responseClone);
+            });
           }
-          if (event.request.mode === 'navigate') {
-            return caches.match('/');
-          }
-          return new Response('Network error occurred', { status: 503, statusText: 'Offline' });
-        });
-      })
+          return networkResponse;
+        })
+        .catch(() => cachedResponse);
+
+      return cachedResponse || fetchPromise;
+    })
   );
 });