Pin binddns-resolver service to a dedicated IP

DNS (UDP/53) can't route via a shared gateway yet (no UDPRoute), so the
service needs its own LoadBalancer address instead of a pool-assigned one.

- pin purelb.io/addresses 198.18.200.7 (common pool)

apps/base/binddns-resolver/cluster.yaml

@@ -0,0 +1,29 @@
+---
+# Recursive resolvers (replaces the 3x Puppet only-resolver servers).
+# Three identical recursive servers; no zone replication.
+apiVersion: bind.unkin.net/v1alpha1
+kind: BindCluster
+metadata:
+  name: resolver
+  namespace: binddns-resolver
+spec:
+  mode: resolver
+  replicas: 3
+  storageClassName: cephrbd-fast-delete
+  storageSize: 1Gi
+  service:
+    type: LoadBalancer
+    annotations:
+      purelb.io/service-group: common
+      purelb.io/addresses: 198.18.200.7
+      external-dns.alpha.kubernetes.io/hostname: resolver.k8s.syd1.au.unkin.net
+  forwarders:
+    - 1.1.1.1
+    - 9.9.9.9
+  resources:
+    requests:
+      cpu: 100m
+      memory: 128Mi
+    limits:
+      cpu: "1"
+      memory: 512Mi

apps/base/binddns-resolver/kustomization.yaml

@@ -0,0 +1,7 @@
+---
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+
+resources:
+  - namespace.yaml
+  - cluster.yaml

apps/base/binddns-resolver/namespace.yaml

@@ -0,0 +1,5 @@
+---
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: binddns-resolver

apps/overlays/au-syd1/binddns-resolver/kustomization.yaml

@@ -0,0 +1,6 @@
+---
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+
+resources:
+  - ../../../base/binddns-resolver