Configure Ingress to route traffic through API7 Gateway

Modified Ingress configuration to route all traffic through the API7
Gateway (gateway-0-1759393614-gateway) instead of directly to application
services. This enables API7's advanced routing, rate limiting, CORS, and
other gateway features.

Changes:
- Updated ingress.yaml template to support gateway backend routing
- Modified values.yaml to route traffic to API7 Gateway service
- Disabled web and api services (now optional) as routing is handled by API7
- Removed nginx.ingress.kubernetes.io/rewrite-target annotation
- Maintained backward compatibility with legacy service-based routing

The Ingress now directs traffic to the API7 Gateway which handles all
routing logic defined in the ADC configuration.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

helm/api7ee-demo-k8s/templates/ingress.yaml

@@ -32,6 +32,14 @@ spec:
           - path: {{ .path }}
             pathType: {{ .pathType }}
             backend:
+              {{- if .gateway }}
+              {{- /* Use API7 Gateway as backend */}}
+              service:
+                name: {{ .gateway.serviceName }}
+                port:
+                  number: {{ .gateway.port | default 80 }}
+              {{- else if .service }}
+              {{- /* Legacy: Use application service as backend */}}
               service:
                 {{- if eq .service "web" }}
                 name: {{ include "api7ee.fullname" $ }}-web
@@ -42,6 +50,7 @@ spec:
                 port:
                   number: {{ $.Values.api.service.port }}
                 {{- end }}
+              {{- end }}
           {{- end }}
     {{- end }}
 {{- end }}