fix: prevent stale cache issues with proper no-cache headers

- Add no-cache headers for index.html, sw.js, registerSW.js, manifest.webmanifest
- Add skipWaiting and clientsClaim to workbox config for immediate SW updates
- This ensures new deployments are picked up immediately without manual cache clearing

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

nginx.conf

@@ -18,7 +18,32 @@ server {
     add_header X-XSS-Protection "1; mode=block" always;
     add_header Referrer-Policy "strict-origin-when-cross-origin" always;
 
-    # Cache static assets
+    # NEVER cache index.html and service worker - always fetch fresh
+    location = /index.html {
+        add_header Cache-Control "no-cache, no-store, must-revalidate";
+        add_header Pragma "no-cache";
+        add_header Expires "0";
+    }
+
+    location = /sw.js {
+        add_header Cache-Control "no-cache, no-store, must-revalidate";
+        add_header Pragma "no-cache";
+        add_header Expires "0";
+    }
+
+    location = /registerSW.js {
+        add_header Cache-Control "no-cache, no-store, must-revalidate";
+        add_header Pragma "no-cache";
+        add_header Expires "0";
+    }
+
+    location = /manifest.webmanifest {
+        add_header Cache-Control "no-cache, no-store, must-revalidate";
+        add_header Pragma "no-cache";
+        add_header Expires "0";
+    }
+
+    # Cache static assets with hashed filenames (immutable)
     location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
         expires 1y;
         add_header Cache-Control "public, immutable";

vite.config.ts

@@ -34,6 +34,9 @@ export default defineConfig(({ mode }) => {
         registerType: 'autoUpdate',
         injectRegister: 'auto',
         workbox: {
+          // Force the service worker to take control immediately
+          skipWaiting: true,
+          clientsClaim: true,
           // Cache all static assets
           globPatterns: ['**/*.{js,css,html,ico,png,svg,woff2,wasm}'],
           // Increase the limit for large chunks (Board is ~8MB with tldraw, automerge, etc.)