Fix quartz Dockerfile for legacy Docker builder

Heredocs in RUN aren't supported without BuildKit.
Move nginx config to separate file and COPY it instead.

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

containers/quartz/Dockerfile

@@ -11,42 +11,11 @@ FROM nginx:alpine
 # Install curl for downloading release assets
 RUN apk add --no-cache curl
 
-# Copy startup script
+# Copy startup script and nginx config
 COPY start.sh /start.sh
+COPY default.conf /etc/nginx/conf.d/default.conf
 RUN chmod +x /start.sh
 
-# Custom nginx config for SPA routing
-RUN cat > /etc/nginx/conf.d/default.conf << 'EOF'
-server {
-    listen 80;
-    server_name _;
-    root /usr/share/nginx/html;
-    index index.html;
-
-    # Enable gzip compression
-    gzip on;
-    gzip_types text/plain text/css application/json application/javascript text/xml application/xml text/javascript;
-
-    # Cache static assets
-    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2)$ {
-        expires 1y;
-        add_header Cache-Control "public, immutable";
-    }
-
-    # SPA fallback - serve index.html for client-side routing
-    location / {
-        try_files $uri $uri/ $uri.html /index.html;
-    }
-
-    # Health check endpoint
-    location /healthz {
-        access_log off;
-        return 200 "ok\n";
-        add_header Content-Type text/plain;
-    }
-}
-EOF
-
 EXPOSE 80
 
 CMD ["/start.sh"]

containers/quartz/default.conf

@@ -0,0 +1,28 @@
+server {
+    listen 80;
+    server_name _;
+    root /usr/share/nginx/html;
+    index index.html;
+
+    # Enable gzip compression
+    gzip on;
+    gzip_types text/plain text/css application/json application/javascript text/xml application/xml text/javascript;
+
+    # Cache static assets
+    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2)$ {
+        expires 1y;
+        add_header Cache-Control "public, immutable";
+    }
+
+    # SPA fallback - serve index.html for client-side routing
+    location / {
+        try_files $uri $uri/ $uri.html /index.html;
+    }
+
+    # Health check endpoint
+    location /healthz {
+        access_log off;
+        return 200 "ok\n";
+        add_header Content-Type text/plain;
+    }
+}