fix(helm): fix dashboard nginx proxy for Kubernetes service names

The dashboard Docker image bakes in a Docker Compose nginx.conf that
uses short service names (api-gateway, catalog, worker) and Docker's
DNS resolver (127.0.0.11) — neither works in Kubernetes.

Add a dashboard-nginx-configmap.yaml that:
- Uses prefix locations (/api-gateway/, /catalog/, /worker/) to avoid
  nginx variables in proxy_pass, which require a resolver directive
- Uses Kubernetes service names (reference-app-api-gateway, etc.)
  resolved via the system resolver at startup

Mount the ConfigMap over /etc/nginx/conf.d/default.conf in the
dashboard deployment to override the baked-in image config.

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

Author: initcron

reference-app/helm/reference-app/templates/dashboard-deployment.yaml

@@ -41,3 +41,11 @@ spec:
             failureThreshold: 2
           resources:
             {{- toYaml .Values.dashboard.resources | nindent 12 }}
+          volumeMounts:
+            - name: nginx-config
+              mountPath: /etc/nginx/conf.d/default.conf
+              subPath: default.conf
+      volumes:
+        - name: nginx-config
+          configMap:
+            name: {{ include "reference-app.fullname" . }}-nginx

reference-app/helm/reference-app/templates/dashboard-nginx-configmap.yaml

@@ -0,0 +1,49 @@
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: {{ include "reference-app.fullname" . }}-nginx
+  labels:
+    {{- include "reference-app.labels" . | nindent 4 }}
+data:
+  default.conf: |
+    server {
+        listen 3000;
+        root /usr/share/nginx/html;
+        index index.html;
+
+        # SPA fallback — serves index.html for all unmatched routes
+        location / {
+            try_files $uri $uri/ /index.html;
+        }
+
+        # Proxy /api-gateway/ → api-gateway service (prefix strip — no variables, resolves at startup)
+        location /api-gateway/ {
+            proxy_pass http://{{ include "reference-app.fullname" . }}-api-gateway:{{ .Values.apiGateway.service.port }}/;
+            proxy_set_header Host $host;
+            proxy_set_header X-Real-IP $remote_addr;
+            proxy_read_timeout 10s;
+        }
+
+        # Proxy /catalog/ → catalog service
+        location /catalog/ {
+            proxy_pass http://{{ include "reference-app.fullname" . }}-catalog:{{ .Values.catalog.service.port }}/;
+            proxy_set_header Host $host;
+            proxy_set_header X-Real-IP $remote_addr;
+            proxy_read_timeout 10s;
+        }
+
+        # Proxy /worker/ → worker service
+        location /worker/ {
+            proxy_pass http://{{ include "reference-app.fullname" . }}-worker:{{ .Values.worker.service.port }}/;
+            proxy_set_header Host $host;
+            proxy_set_header X-Real-IP $remote_addr;
+            proxy_read_timeout 10s;
+        }
+
+        # Health check endpoint for container probes
+        location /nginx-health {
+            access_log off;
+            return 200 "ok\n";
+            add_header Content-Type text/plain;
+        }
+    }