fix: remove unused vault PVC from memory deployment

Memory service stores in pgvector, not local files.
PVC was RWO causing multi-node scheduling failures with 2 replicas.
MEM_HOME points to /tmp (emptyDir) for any scratch needs.

k8s/app/deployment.yaml

@@ -70,7 +70,7 @@ spec:
             - name: MEM_PORT
               value: "8080"
             - name: MEM_HOME
-              value: "/data"
+              value: "/tmp"
           args:
             - serve
             - --port
@@ -97,14 +97,9 @@ spec:
             initialDelaySeconds: 5
             periodSeconds: 10
           volumeMounts:
-            - name: data
-              mountPath: /data
             - name: tmp
               mountPath: /tmp
       volumes:
-        - name: data
-          persistentVolumeClaim:
-            claimName: poimen-memory-vault
         - name: tmp
           emptyDir:
             sizeLimit: 64Mi

k8s/app/kustomization.yaml

@@ -2,7 +2,7 @@ apiVersion: kustomize.config.k8s.io/v1beta1
 kind: Kustomization
 namespace: poimen
 resources:
-  - vault-pvc.yaml
+  # vault-pvc.yaml removed — memory service uses pgvector, not local storage
   - deployment.yaml
   - service.yaml
   - obsidian.yaml