feat: add production PWA service worker

public/sw.js

@@ -0,0 +1,53 @@
+const CACHE_NAME = "agendamax-shell-v1";
+const SHELL_URLS = ["/", "/manifest.webmanifest", "/favicon.svg", "/icon-192.png", "/icon-512.png"];
+
+self.addEventListener("install", (event) => {
+  event.waitUntil(
+    caches.open(CACHE_NAME).then((cache) => cache.addAll(SHELL_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 || url.pathname.startsWith("/api/")) return;
+
+  if (request.mode === "navigate") {
+    event.respondWith(
+      fetch(request)
+        .then((response) => {
+          if (response.ok) {
+            const copy = response.clone();
+            void caches.open(CACHE_NAME).then((cache) => cache.put(request, copy));
+          }
+          return response;
+        })
+        .catch(() => caches.match("/"))
+    );
+    return;
+  }
+
+  const cacheableDestination = new Set(["script", "style", "image", "font", "manifest", "worker"]);
+  if (!cacheableDestination.has(request.destination)) return;
+
+  event.respondWith(
+    caches.match(request).then((cached) => {
+      if (cached) return cached;
+      return fetch(request).then((response) => {
+        if (response.ok) {
+          const copy = response.clone();
+          void caches.open(CACHE_NAME).then((cache) => cache.put(request, copy));
+        }
+        return response;
+      });
+    })
+  );
+});