feat: add ReferenceGrants for cross-namespace routing

apps/traefik.yaml

@@ -15,7 +15,8 @@ spec:
           kubernetesGateway:
             enabled: true
           kubernetesCRD:
-            enabled: false
+            enabled: true
+            allowCrossNamespace: true
           kubernetesIngress:
             enabled: false
         gateway:

manifests/reference-grants.yaml

@@ -0,0 +1,27 @@
+apiVersion: gateway.networking.k8s.io/v1beta1
+kind: ReferenceGrant
+metadata:
+  name: allow-traefik-gateway
+  namespace: longhorn-system
+spec:
+  from:
+    - group: gateway.networking.k8s.io
+      kind: HTTPRoute
+      namespace: longhorn-system
+  to:
+    - group: ""
+      kind: Service
+---
+apiVersion: gateway.networking.k8s.io/v1beta1
+kind: ReferenceGrant
+metadata:
+  name: allow-traefik-gateway
+  namespace: kube-system
+spec:
+  from:
+    - group: gateway.networking.k8s.io
+      kind: HTTPRoute
+      namespace: kube-system
+  to:
+    - group: ""
+      kind: Service