Grafana dashboard UID too long

Not sure if this is a problem just on my configuration but I'm getting the following error from grafana when deploying the dashboard through the helm chart:

```
logger=provisioning.dashboard type=file name=sidecarProvider t=2026-08-17T06:31:20.942905212Z level=error msg="failed to save dashboard" file=/tmp/dashboards/dashboard.json error="uid too long, max 40 characters"
```

The dashboard uid seems to be 42 characters, so it appears that this hits a grafana internal limit.

Ah I see, the dashboard uses `"uid": "{{ include "xpumd.fullname" . }}-dashboard"`. This should probably just be a static uid, there is no reason to have a dynamic uid imo.

Start by locating the dashboard template in the Helm chart that uses the `xpumd.fullname` expression for its UID, then inspect how the dashboard is deployed. Done means Grafana accepts the dashboard UID within its 40-character limit when deploying through the chart.

Written by the indexing model from the issue text.