Set up initial frontend with Vite and integrated Docker for full-stack build

frontend/public/sw.js

@@ -0,0 +1,32 @@
+const CACHE = 'budget-commun-v3'
+const ASSETS = ['/', '/index.html', '/manifest.json']
+
+self.addEventListener('install', e => {
+  e.waitUntil(caches.open(CACHE).then(c => c.addAll(ASSETS)))
+  self.skipWaiting()
+})
+
+self.addEventListener('activate', e => {
+  e.waitUntil(
+    caches.keys().then(keys =>
+      Promise.all(keys.filter(k => k !== CACHE).map(k => caches.delete(k)))
+    )
+  )
+  self.clients.claim()
+})
+
+self.addEventListener('fetch', e => {
+  // API : réseau uniquement, jamais de cache
+  if (e.request.url.includes('/api/')) return
+
+  // Assets statiques : network first → cache en fallback offline
+  e.respondWith(
+    fetch(e.request)
+      .then(response => {
+        const clone = response.clone()
+        caches.open(CACHE).then(c => c.put(e.request, clone))
+        return response
+      })
+      .catch(() => caches.match(e.request))
+  )
+})