"Logs for this span" does not filter by trace_id, shows all logs for the service instead #779

Description

When clicking "Logs for this span" on a span in the Traces Drilldown app, the resulting Loki query only filters by service_name (and service_namespace), without including a trace_id filter. This causes all logs from the service to be shown instead of only the logs correlated with the selected span/trace.

Steps to Reproduce

1. Open Traces Drilldown app
2. Select a trace
3. Select a span
4. Click "Logs for this span"

Expected Behavior

The Loki query should include a trace_id filter, e.g.:

{`service_name`="frontend", `service_namespace`="demo"} | `trace_id` = "<`trace_id`>"

Actual Behavior

The generated Loki query only filters by service labels:

{`service_name`="frontend", `service_namespace`="demo"}

No trace_id filter is applied, resulting in all logs from the service being shown.

Additional Context

• trace_id is stored as Loki structured metadata (not a stream label), which is why {trace_id="..."} cannot be used as a stream selector. A label filter (| trace_id = "...") is required instead.
• The Tempo datasource "Trace to logs" custom query configuration is ignored by the Traces Drilldown app.
• Grafana version: 13.1.0 (Cloud Advanced)
• Traces Drilldown app: grafana-exploretraces-app