update nginx config

frontend/nginx.conf

@@ -12,6 +12,9 @@ http {
     gzip_vary on;
     gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript;
 
+    # Set maximum request body size to 50MB to handle large drawings with embedded images
+    client_max_body_size 50M;
+
     server {
         listen 80;
         server_name localhost;
@@ -29,6 +32,18 @@ http {
             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;
+            
+            # Buffer and timeout settings for large payloads
+            proxy_buffering on;
+            proxy_buffer_size 4k;
+            proxy_buffers 8 4k;
+            proxy_busy_buffers_size 8k;
+            client_body_buffer_size 128k;
+            
+            # Timeouts for large uploads (300 seconds)
+            proxy_connect_timeout 300s;
+            proxy_send_timeout 300s;
+            proxy_read_timeout 300s;
         }
 
         # WebSocket proxy for Socket.IO