[BUG] Netdata and Grafana integration - queries send empty scope.nodes and fail with 400 Bad Request #1132

In Grafana, the Netdata datasource plugin does not populate the Nodes and Instances selectors (they remain empty), which prevents building dashboards/variables. When running a query anyway, Grafana sends a request to the Netdata Cloud /base/v3/.../data endpoint where scope.nodes is an empty array. The API responds with 400 Bad Request.

This appears to be either:

The plugin failing to fetch/resolve nodes/instances for the chosen Space/Room, or
The plugin composing an invalid request when nodes/instances are not available (e.g., should omit scope.nodes or use "*" semantics consistently).

{
"errorMsgKey": "ErrBadRequest",
"errorMessage": "Bad Request",
"errorCode": "1BIKRyPlV9-124244066"
}