fix: restore service worker and add manifest icons

public/sw.js

@@ -1,26 +1,16 @@
 /* eslint-disable no-undef */
 
-// Self-destructing service worker.
-//
-// The previous version of this file used a cache-first strategy with no
-// dev-mode guard, which pinned stale JS/HTML chunks until a hard reload.
-// This replacement unregisters itself and wipes all caches as soon as the
-// browser picks it up. Browsers re-fetch sw.js on every navigation to check
-// for updates, so any client running the old worker will swap to this one
-// on their next page load and then lose the worker entirely.
+// Minimal service worker – satisfies the PWA installability requirement
+// without caching any assets. All requests fall through to the network,
+// so there is no risk of serving stale chunks after a deployment.
 
 self.addEventListener("install", () => {
   self.skipWaiting();
 });
 
 self.addEventListener("activate", (event) => {
-  event.waitUntil(
-    (async () => {
-      const cacheNames = await caches.keys();
-      await Promise.all(cacheNames.map((name) => caches.delete(name)));
-      await self.registration.unregister();
-      const clients = await self.clients.matchAll({ type: "window" });
-      clients.forEach((client) => client.navigate(client.url));
-    })(),
-  );
+  event.waitUntil(self.clients.claim());
 });
+
+// Network-only fetch handler – no caching.
+self.addEventListener("fetch", () => {});