[mlrun] Support ReadWriteMany access mode when worker replicas > 0

- Add helper function to automatically set PVC access mode to ReadWriteMany when api.worker.minReplicas > 0
- This allows both chief and worker pods to share the same volume
- Falls back to configured accessMode (default: ReadWriteOnce) when no workers are deployed
- Bump chart version to 0.11.16

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: liranbg

stable/mlrun/Chart.yaml

@@ -1,6 +1,6 @@
 apiVersion: v1
 name: mlrun
-version: 0.11.15
+version: 0.11.16
 appVersion: 1.10.1
 description: Machine Learning automation and tracking
 sources:

stable/mlrun/templates/_helpers.tpl

@@ -438,3 +438,20 @@ Resolve the MLRun DB DSN
     {{- printf .Values.httpDB.dsn -}}
   {{- end -}}
 {{- end -}}
+
+{{/*
+Resolve the API persistence access mode
+- If accessMode is explicitly set, use it
+- Otherwise, infer from worker replicas:
+  - ReadWriteMany when worker replicas > 0 (multiple pods need shared volume)
+  - ReadWriteOnce when worker replicas == 0 (single pod)
+*/}}
+{{- define "mlrun.api.persistence.accessMode" -}}
+  {{- if .Values.api.persistence.accessMode -}}
+    {{- printf .Values.api.persistence.accessMode -}}
+  {{- else if gt (int .Values.api.worker.minReplicas) 0 -}}
+    {{- print "ReadWriteMany" -}}
+  {{- else -}}
+    {{- print "ReadWriteOnce" -}}
+  {{- end -}}
+{{- end -}}

stable/mlrun/templates/mlrun-api-pvc.yaml

@@ -11,7 +11,7 @@ metadata:
 {{- end }}
 spec:
   accessModes:
-    - {{ .Values.api.persistence.accessMode | quote }}
+    - {{ include "mlrun.api.persistence.accessMode" . | quote }}
   resources:
     requests:
       storage: {{ .Values.api.persistence.size | quote }}

stable/mlrun/values.yaml

@@ -60,7 +60,11 @@ api:
     enabled: false
     existingClaim:
     storageClass:
-    accessMode: "ReadWriteOnce"
+    # Access mode for the PVC. If empty, automatically inferred:
+    # - ReadWriteMany when worker.minReplicas > 0 (multiple pods need shared volume)
+    # - ReadWriteOnce when worker.minReplicas == 0 (single pod)
+    # If explicitly set, the provided value is used regardless of worker count.
+    accessMode: ""
     size: "8Gi"
     annotations: ~