[linstor] Enable auto-diskful for diskless nodes (#1826)

## What this PR does

Enable DRBD auto-diskful options to automatically convert diskless nodes
to diskful when they remain in Primary state for an extended period.

### How it works

When LINSTOR is integrated with Kubernetes, the platform may schedule
workloads on nodes that don't have local storage replicas. In such
cases, DRBD operates in "diskless" mode, accessing data over the network
from nodes that have actual disk replicas.

The `auto-diskful` feature addresses this by:

1. **Monitoring Primary state duration**: When a diskless node holds a
DRBD resource in Primary state (actively using the volume) for more than
the configured time (30 minutes), LINSTOR automatically creates a local
disk replica on that node.

2. **Automatic cleanup**: With `auto-diskful-allow-cleanup` enabled,
when the resource is no longer in Primary state on that node, LINSTOR
can automatically remove the disk replica that was created, freeing up
storage space.

### Configuration

- `DrbdOptions/auto-diskful: 30` — Convert diskless to diskful after 30
minutes in Primary state
- `DrbdOptions/auto-diskful-allow-cleanup: true` — Allow automatic
removal of auto-created replicas when no longer needed

### Benefits

- Improves I/O performance for long-running workloads by creating local
replicas
- Reduces network traffic for frequently accessed data
- Automatic cleanup prevents storage waste from temporary replicas

### Release note

```release-note
[linstor] Enable auto-diskful to automatically create local replicas on diskless nodes that hold volumes in Primary state for more than 30 minutes, improving I/O performance for long-running workloads.
```

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
* Introduced an "auto diskful" option to automatically manage diskful
resources with configurable interval and optional cleanup.
* **Chores**
* Added default configuration values to enable and time the auto-diskful
behavior and to control automatic cleanup.

<sub>✏️ Tip: You can customize this high-level summary in your review
settings.</sub>
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/system/linstor/templates/cluster.yaml

@@ -14,6 +14,12 @@ spec:
       name: linstor-api-ca
       kind: Issuer
   properties:
+  {{- if .Values.linstor.autoDiskful.enabled }}
+  - name: DrbdOptions/auto-diskful
+    value: {{ .Values.linstor.autoDiskful.minutes | quote }}
+  - name: DrbdOptions/auto-diskful-allow-cleanup
+    value: {{ .Values.linstor.autoDiskful.allowCleanup | quote }}
+  {{- end }}
   - name: DrbdOptions/Net/connect-int
     value: "15"
   - name: DrbdOptions/Net/ping-int

packages/system/linstor/values.yaml

@@ -2,3 +2,9 @@ piraeusServer:
   image:
     repository: ghcr.io/cozystack/cozystack/piraeus-server
     tag: latest@sha256:417532baa2801288147cd9ac9ae260751c1a7754f0b829725d09b72a770c111a
+
+linstor:
+  autoDiskful:
+    enabled: true
+    minutes: 30
+    allowCleanup: true