Add dashboard PWA shell and status UX

apps/dashboard/public/sw.js

@@ -0,0 +1,78 @@
+const CACHE_NAME = 'ejclaw-dashboard-v1';
+const PRECACHE_URLS = [
+  '/',
+  '/index.html',
+  '/offline.html',
+  '/manifest.webmanifest',
+  '/icons/icon-192.png',
+  '/icons/icon-512.png',
+  '/icons/icon-192.svg',
+  '/icons/icon-512.svg',
+];
+
+self.addEventListener('install', (event) => {
+  event.waitUntil(
+    caches
+      .open(CACHE_NAME)
+      .then((cache) => cache.addAll(PRECACHE_URLS))
+      .then(() => self.skipWaiting()),
+  );
+});
+
+self.addEventListener('activate', (event) => {
+  event.waitUntil(
+    caches
+      .keys()
+      .then((keys) =>
+        Promise.all(
+          keys
+            .filter((key) => key !== CACHE_NAME)
+            .map((key) => caches.delete(key)),
+        ),
+      )
+      .then(() => self.clients.claim()),
+  );
+});
+
+self.addEventListener('fetch', (event) => {
+  const { request } = event;
+  const url = new URL(request.url);
+
+  if (request.method !== 'GET' || url.origin !== self.location.origin) {
+    return;
+  }
+
+  if (url.pathname.startsWith('/api/')) {
+    event.respondWith(fetch(request));
+    return;
+  }
+
+  if (request.mode === 'navigate') {
+    event.respondWith(
+      fetch(request)
+        .then((response) => {
+          const copy = response.clone();
+          caches.open(CACHE_NAME).then((cache) => cache.put('/', copy));
+          return response;
+        })
+        .catch(() =>
+          caches
+            .match('/')
+            .then((cached) => cached || caches.match('/offline.html')),
+        ),
+    );
+    return;
+  }
+
+  event.respondWith(
+    caches.match(request).then((cached) => {
+      if (cached) return cached;
+      return fetch(request).then((response) => {
+        if (!response.ok) return response;
+        const copy = response.clone();
+        caches.open(CACHE_NAME).then((cache) => cache.put(request, copy));
+        return response;
+      });
+    }),
+  );
+});