Add eWeLink CUBE OS chart

Bridges eWeLink Wi-Fi and Zigbee devices into Matter (HomeKit,
Google Home, Alexa, Home Assistant). Uses a Multus macvlan interface
instead of hostNetwork, since CUBE OS hardcodes host port 80/1883
which would otherwise collide with Traefik on the same node.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BU7b2w8XZPbD7uXRfjKwcm

cubeos/templates/pvc.yaml

@@ -0,0 +1,18 @@
+{{- if and .Values.persistence.enabled (not .Values.persistence.existingClaim) }}
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: {{ .Release.Name }}-data
+  labels:
+    app.kubernetes.io/name: {{ .Chart.Name }}
+    app.kubernetes.io/instance: {{ .Release.Name }}
+spec:
+  accessModes:
+    {{- toYaml .Values.persistence.accessModes | nindent 4 }}
+  {{- with .Values.persistence.storageClass }}
+  storageClassName: {{ . }}
+  {{- end }}
+  resources:
+    requests:
+      storage: {{ .Values.persistence.size }}
+{{- end }}