feat(agent-pod): deploy pi coding-agent pod for in-cluster harness

Namespace + Deployment (2-4 CPU, 4-8Gi mem) running node:20-slim with
pi installed at startup, wired to the homelab-ornith/reasoning/qwen
model providers via the existing model-invoke-apikey. Placeholder
node:20-slim image for now, real harness image to follow.

k8s/apps/agent-pod/deployment.yaml

@@ -0,0 +1,46 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: agent-pod
+  namespace: agent-pod
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: agent-pod
+  template:
+    metadata:
+      labels:
+        app: agent-pod
+    spec:
+      containers:
+        - name: pi
+          image: node:20-slim
+          command:
+            - sh
+            - -c
+            - "npm install -g @earendil-works/[email protected] && sleep infinity"
+          resources:
+            requests:
+              cpu: "2"
+              memory: 4Gi
+            limits:
+              cpu: "4"
+              memory: 8Gi
+          volumeMounts:
+            - name: pi-config
+              mountPath: /root/.pi/config.json
+              subPath: config.json
+            - name: pi-config
+              mountPath: /root/.pi/agent/settings.json
+              subPath: settings.json
+            - name: pi-models
+              mountPath: /root/.pi/agent/models.json
+              subPath: models.json
+      volumes:
+        - name: pi-config
+          configMap:
+            name: pi-config
+        - name: pi-models
+          secret:
+            secretName: pi-models