trace: refactor SpanURL
Created by: tsenart
This commit refactors trace.SpanURL into trace.ID, trace.IDFromSpan and trace.URL. It also adds support for Grafana Cloud trace URLs (instead of TRACE_BASE_URL, which didn't pan out).
Created by: tsenart
This commit refactors trace.SpanURL into trace.ID, trace.IDFromSpan and trace.URL. It also adds support for Grafana Cloud trace URLs (instead of TRACE_BASE_URL, which didn't pan out).