feat: PWA (#15)

add for PWA capability

public/sw.js

@@ -0,0 +1,56 @@
+// public/sw.js
+const CACHE_NAME = 'app-cache-v1';
+const ASSETS_TO_CACHE = [
+    '/',
+    '/manifest.json',
+    // Add paths to your main CSS and JS files here
+    // e.g., '/build/app.css', '/build/app.js'
+];
+
+// Install Event: Cache core static assets
+self.addEventListener('install', event => {
+    event.waitUntil(
+        caches.open(CACHE_NAME)
+        .then(cache => {
+            return cache.addAll(ASSETS_TO_CACHE);
+        })
+    );
+    self.skipWaiting();
+});
+
+// Activate Event: Clean up old caches if you change the CACHE_NAME version
+self.addEventListener('activate', event => {
+    event.waitUntil(
+        caches.keys().then(cacheNames => {
+            return Promise.all(
+                cacheNames.map(cache => {
+                    if (cache !== CACHE_NAME) {
+                        return caches.delete(cache);
+                    }
+                })
+            );
+        })
+    );
+    self.clients.claim();
+});
+
+// Fetch Event: Network First, Fallback to Cache
+self.addEventListener('fetch', event => {
+    // Only cache GET requests
+    if (event.request.method !== 'GET') return;
+
+    event.respondWith(
+        fetch(event.request)
+            .then(networkResponse => {
+                // If the network request succeeds, clone it and put it in the cache
+                return caches.open(CACHE_NAME).then(cache => {
+                    cache.put(event.request, networkResponse.clone());
+                    return networkResponse;
+                });
+            })
+            .catch(() => {
+                // If the network fails (offline), try to serve from cache
+                return caches.match(event.request);
+            })
+    );
+});