feat: Add ResourceIndexPolicy for Domain, DNSZone, Contact, and Note (#215)

## Summary

- Deploys `ResourceIndexPolicy` resources for four additional types so
they appear in `search.miloapis.com` results alongside the existing User
policy
- Indexes searchable fields on Domain, DNSZone, Contact, and Note
resources
- Wires all four policies into the `search.miloapis.com` kustomization
component

## Details

| Resource | Group | Version | Indexed fields |
|---|---|---|---|
| Domain | `networking.datumapis.com` | `v1alpha` | `domainName`,
`status.apex`, `status.nameservers[0].hostname`, registrar/registry
names |
| DNSZone | `dns.networking.miloapis.com` | `v1alpha1` | `domainName`,
`dnsZoneClassName` |
| Contact | `notification.miloapis.com` | `v1alpha1` | `givenName`,
`familyName`, email address |
| Note | `notes.miloapis.com` | `v1alpha1` | `content`, `nextAction` |

**Note:** Contact uses `spec.givenName`/`spec.familyName` — the issue
sample referenced `firstName`/`lastName` which does not match the actual
milo type definition.

**Note:** Domain version is `v1alpha` (no trailing `1`) — this is
intentional. The `network-services-operator` has two separate API
packages: `api/v1alpha` (Domain) and `api/v1alpha1` (Connector,
ConnectorAdvertisement, ConnectorClass).

Closes #214

## Test plan

- [ ] Verify search returns Domain resources after deploy
- [ ] Verify search returns DNSZone resources after deploy
- [ ] Verify search returns Contact resources after deploy
- [ ] Verify search returns Note resources after deploy
- [ ] Confirm no regressions on existing User search results

Author: kevwilliams

config/services/search.miloapis.com/contact-resourceindexpolicy.yaml

@@ -0,0 +1,22 @@
+apiVersion: search.miloapis.com/v1alpha1
+kind: ResourceIndexPolicy
+metadata:
+  name: contact-resource-index-policy
+spec:
+  fields:
+  - path: .metadata.name
+    searchable: true
+  - path: .metadata.annotations["kubernetes.io/display-name"]
+    searchable: true
+  - path: .metadata.annotations["kubernetes.io/description"]
+    searchable: true
+  - path: .spec.givenName
+    searchable: true
+  - path: .spec.familyName
+    searchable: true
+  - path: .spec.email
+    searchable: true
+  targetResource:
+    group: notification.miloapis.com
+    kind: Contact
+    version: v1alpha1

config/services/search.miloapis.com/dnszone-resourceindexpolicy.yaml

@@ -0,0 +1,18 @@
+apiVersion: search.miloapis.com/v1alpha1
+kind: ResourceIndexPolicy
+metadata:
+  name: dnszone-resource-index-policy
+spec:
+  fields:
+  - path: .metadata.name
+    searchable: true
+  - path: .metadata.annotations["kubernetes.io/display-name"]
+    searchable: true
+  - path: .metadata.annotations["kubernetes.io/description"]
+    searchable: true
+  - path: .spec.domainName
+    searchable: true
+  targetResource:
+    group: dns.networking.miloapis.com
+    kind: DNSZone
+    version: v1alpha1

config/services/search.miloapis.com/domain-resourceindexpolicy.yaml

@@ -0,0 +1,18 @@
+apiVersion: search.miloapis.com/v1alpha1
+kind: ResourceIndexPolicy
+metadata:
+  name: domain-resource-index-policy
+spec:
+  fields:
+  - path: .metadata.name
+    searchable: true
+  - path: .metadata.annotations["kubernetes.io/display-name"]
+    searchable: true
+  - path: .metadata.annotations["kubernetes.io/description"]
+    searchable: true
+  - path: .spec.domainName
+    searchable: true
+  targetResource:
+    group: networking.datumapis.com
+    kind: Domain
+    version: v1alpha

config/services/search.miloapis.com/kustomization.yaml

@@ -3,6 +3,9 @@ kind: Component
 
 resources:
   - user-resourceindexpolicy.yaml
+  - domain-resourceindexpolicy.yaml
+  - dnszone-resourceindexpolicy.yaml
+  - contact-resourceindexpolicy.yaml
 
 # Use explicit sorting options so we can guarantee order in which resources are
 # applied.