Increase nginx client_max_body_size to 100m for image uploads

Default 1MB limit caused 413 errors for raw images (14MB+).
Also add proxy_read_timeout for large uploads.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/nginx.conf

@@ -4,6 +4,9 @@ server {
     root /usr/share/nginx/html;
     index index.html;
 
+    # Tillat store bildeopplastinger (råbilder kan være 20MB+)
+    client_max_body_size 100m;
+
     # SPA: alle ruter går til index.html
     location / {
         try_files $uri $uri/ /index.html;
@@ -14,5 +17,6 @@ server {
         proxy_pass http://backend:8000;
         proxy_set_header Host $host;
         proxy_set_header X-Real-IP $remote_addr;
+        proxy_read_timeout 120s;
     }
 }