Fix viewer proxy path handling in Nginx configuration

Dockerfile

@@ -100,9 +100,9 @@ http {\n\
             proxy_set_header X-Forwarded-Proto $scheme;\n\
         }\n\
         \n\
-        # Viewer route\n\
+        # Viewer route - explicitly handle the viewer path\n\
         location /viewer/ {\n\
-            proxy_pass http://viewer;\n\
+            proxy_pass http://viewer/viewer/;\n\
             proxy_http_version 1.1;\n\
             proxy_set_header Upgrade $http_upgrade;\n\
             proxy_set_header Connection $connection_upgrade;\n\

cadviewer.py

@@ -201,7 +201,7 @@ with ui.splitter().classes(
             logger.info(f"Space URL: {space_url}")
             
             # Construct the viewer URL - use relative path for both local and Space environments
-            viewer_url = "/viewer"  # Changed to match Nginx configuration
+            viewer_url = "/viewer/"  # Add trailing slash back for proper path handling
             logger.info(f"Using viewer URL: {viewer_url}")
             
             ocpcv = (