chore: remove unused obsidian-vault PVC

No pods mount it. Obsidian integration was retired in favor of memory graph.

k8s/infra/databases/kustomization.yaml

@@ -10,4 +10,3 @@ resources:
   - temporal-db.yaml
   - memory-db.yaml
   - paperless-db.yaml
-  - obsidian-vault-pvc.yaml

k8s/infra/databases/obsidian-vault-pvc.yaml

@@ -1,18 +0,0 @@
----
-# Obsidian vault PVC — shared storage for REST API + UI pods
-# ReadWriteMany so both obsidian-server and obsidian-ui can mount simultaneously
-apiVersion: v1
-kind: PersistentVolumeClaim
-metadata:
-  name: obsidian-vault
-  namespace: poimen
-  labels:
-    app.kubernetes.io/name: obsidian-server
-    app.kubernetes.io/part-of: poimen-memory
-spec:
-  accessModes:
-    - ReadWriteMany
-  storageClassName: longhorn
-  resources:
-    requests:
-      storage: 10Gi