feat(wiki): wire the Anthropic answer-model key from apps/ai/wiki-anthropic

Wiki PR #7 adds the questions endpoint backed by the Anthropic Messages API.
The key arrives as Wiki__AnswerModels__Models__claude-sonnet__ApiKey via an
ExternalSecret; the secretRef is optional so the pod keeps starting while the
OpenBao key does not exist yet. Namespace egress already admits world, so no
CNP change.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

kubernetes/apps/wiki/deployment.yaml

@@ -79,6 +79,9 @@ spec:
                 name: wiki-api-keys
             - secretRef:
                 name: wiki-typesafe
+            - secretRef:
+                name: wiki-anthropic
+                optional: true
           ports:
             - name: http
               containerPort: 8080

kubernetes/apps/wiki/externalsecrets.yaml

@@ -61,6 +61,26 @@ spec:
         key: apps/ai/wiki-typesafe
         property: api_key
 ---
+# Answer model: Wiki:AnswerModels:Models:claude-sonnet. The pod starts without it (optional
+# secretRef); the questions endpoint answers 503 until the key is placed.
+apiVersion: external-secrets.io/v1
+kind: ExternalSecret
+metadata:
+  name: wiki-anthropic
+  namespace: ai
+spec:
+  refreshInterval: 1h
+  secretStoreRef:
+    kind: ClusterSecretStore
+    name: openbao
+  target:
+    name: wiki-anthropic
+  data:
+    - secretKey: Wiki__AnswerModels__Models__claude-sonnet__ApiKey
+      remoteRef:
+        key: apps/ai/wiki-anthropic
+        property: api_key
+---
 # BasicAuth users for the machine door; same OpenBao key as the Python service used.
 apiVersion: external-secrets.io/v1
 kind: ExternalSecret