fix: Implement Network-First SW strategy, no-cache headers in Nginx for index.html/sw.js, and auto 401 token cleanup to fix post-redeploy stale cache issues

frontend/nginx.conf

@@ -9,8 +9,22 @@ server {
     gzip on;
     gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript;
 
+    # Prevent caching of index.html and sw.js so redeploys fetch new assets immediately
+    location ~* (index\.html|sw\.js|manifest\.json)$ {
+        add_header Cache-Control "no-cache, no-store, must-revalidate";
+        add_header Pragma "no-cache";
+        add_header Expires "0";
+    }
+
+    # Cache immutable static assets with hash (js, css, images) for performance
+    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff2)$ {
+        expires 1y;
+        add_header Cache-Control "public, max-age=31536000, immutable";
+    }
+
     location / {
         try_files $uri $uri/ /index.html;
+        add_header Cache-Control "no-cache, no-store, must-revalidate";
     }
 
     location /api/ {
@@ -31,5 +45,9 @@ server {
 
     location /static/ {
         proxy_pass http://backend:8000/static/;
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
     }
 }