fix(telemetry): revert collector group-label build (cloud + Alloy configs)

The legend now uses raw labels in the dashboard Display name (see the paired
dashboard commit), so the collector no longer needs to build resource_group /
iac_group. Those derived labels also could not survive the dashboards' sum by()
aggregation, which is why the grouped approach was dropped.

Revert transform/legendgroups and its transform/cloudlabels datapoint copies
from the Grafana Cloud collector config and the in-repo Alloy config; both files
are now identical to their pre-change state.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

docker/telemetry/alloy/config.alloy

@@ -151,15 +151,6 @@ otelcol.processor.transform "tier" {
       `delete_key(attributes, "telemetry.sdk.language")`,
       `delete_key(attributes, "telemetry.sdk.name")`,
       `delete_key(attributes, "telemetry.sdk.version")`,
-      // Grouped legend labels must be built here too, not only in
-      // metric_statements: span-derived RED metrics (span_calls_total,
-      // span_duration_*) are produced by the spanmetrics connector from these
-      // TRACES and go straight to the batch processor, bypassing the metric
-      // resource statements. Building the labels on the span resource keeps
-      // span-based dashboard panels' legends consistent with native metrics.
-      `set(attributes["resource_group"], Concat(["[", attributes["service.instance.id"], "]"], "")) where attributes["service.instance.id"] != nil and attributes["service.instance.id"] != ""`,
-      `set(attributes["resource_group"], Concat(["[", attributes["service.instance.id"], ", ", attributes["xrpl.network.type"], "]"], "")) where attributes["service.instance.id"] != nil and attributes["service.instance.id"] != "" and attributes["xrpl.network.type"] != nil and attributes["xrpl.network.type"] != ""`,
-      `set(attributes["iac_group"], Concat(["[", Concat([attributes["xrpl.branch"], attributes["xrpl.node.role"], attributes["xrpl.work.item"]], ", "), "]"], "")) where attributes["xrpl.branch"] != nil and attributes["xrpl.branch"] != "" and attributes["xrpl.node.role"] != nil and attributes["xrpl.node.role"] != "" and attributes["xrpl.work.item"] != nil and attributes["xrpl.work.item"] != ""`,
     ]
   }
 
@@ -172,21 +163,6 @@ otelcol.processor.transform "tier" {
       `delete_key(attributes, "telemetry.sdk.language")`,
       `delete_key(attributes, "telemetry.sdk.name")`,
       `delete_key(attributes, "telemetry.sdk.version")`,
-      // Grouped legend labels for the Grafana dashboards (kept in sync with the
-      // reference collector's transform/legendgroups). The Cloud gateway
-      // promotes these resource attributes to Prometheus labels server-side.
-      // Brackets and ", " separators are baked into the VALUE (e.g.
-      // "[node, mainnet]") so the dashboard Display name needs no literal
-      // brackets and an absent group renders as nothing.
-      //   * resource_group: "[node]" or "[node, network]".
-      //   * iac_group: "[branch, role, work-item]". A generic node like this one
-      //     does not set those attrs, so the guard leaves iac_group unset; it is
-      //     built only on perf-comparison nodes. The guard checks != "" as well
-      //     as != nil because OTTL Concat emits "<nil>"/a stray separator for an
-      //     absent or empty element.
-      `set(attributes["resource_group"], Concat(["[", attributes["service.instance.id"], "]"], "")) where attributes["service.instance.id"] != nil and attributes["service.instance.id"] != ""`,
-      `set(attributes["resource_group"], Concat(["[", attributes["service.instance.id"], ", ", attributes["xrpl.network.type"], "]"], "")) where attributes["service.instance.id"] != nil and attributes["service.instance.id"] != "" and attributes["xrpl.network.type"] != nil and attributes["xrpl.network.type"] != ""`,
-      `set(attributes["iac_group"], Concat(["[", Concat([attributes["xrpl.branch"], attributes["xrpl.node.role"], attributes["xrpl.work.item"]], ", "), "]"], "")) where attributes["xrpl.branch"] != nil and attributes["xrpl.branch"] != "" and attributes["xrpl.node.role"] != nil and attributes["xrpl.node.role"] != "" and attributes["xrpl.work.item"] != nil and attributes["xrpl.work.item"] != ""`,
     ]
   }
 

docker/telemetry/otel-collector-config.grafanacloud.yaml

@@ -123,34 +123,6 @@ processors:
           - set(attributes["service_instance_id"], resource.attributes["service.instance.id"])
           - set(attributes["deployment_environment"], resource.attributes["deployment.environment"])
           - set(attributes["xrpl_network_type"], resource.attributes["xrpl.network.type"])
-          # Copy the grouped legend labels built by transform/legendgroups onto
-          # datapoint attributes too (same reason as the tier attrs above: Cloud
-          # OTLP ingest does not promote resource attributes to labels). Guarded
-          # so a group absent on the resource is not created as an empty label.
-          - set(attributes["resource_group"], resource.attributes["resource_group"]) where resource.attributes["resource_group"] != nil
-          - set(attributes["iac_group"], resource.attributes["iac_group"]) where resource.attributes["iac_group"] != nil
-  # Build grouped legend labels from the tier / perf-iac resource attributes so
-  # dashboards reference one pre-built label per group. On the local scrape these
-  # are promoted to labels by resource_to_telemetry_conversion; on the Cloud path
-  # transform/cloudlabels (above) copies them onto datapoint attributes.
-  # The BRACKETS and comma separators are baked into the label VALUE here (e.g.
-  # "[node, mainnet]") rather than added in the dashboard Display name: a template
-  # like "... [${__field.labels.iac_group}]" renders an empty "[]" when the label
-  # is absent, and Grafana's renameByRegex runs pre-interpolation so it cannot
-  # strip it. Baking brackets into the value means an absent group is just an
-  # absent label -> the Display name renders nothing for it.
-  #   - iac_group: "[branch, role, work-item]", built only on perf runs.
-  #   - resource_group: "[node]" or "[node, network]".
-  # Guards check != nil and != "" because OTTL Concat renders "<nil>" for an
-  # absent attribute and the perf-iac collector stamps these with an empty-string
-  # default outside a comparison run.
-  transform/legendgroups:
-    metric_statements:
-      - context: resource
-        statements:
-          - set(attributes["iac_group"], Concat(["[", Concat([attributes["xrpl.branch"], attributes["xrpl.node.role"], attributes["xrpl.work.item"]], ", "), "]"], "")) where attributes["xrpl.branch"] != nil and attributes["xrpl.branch"] != "" and attributes["xrpl.node.role"] != nil and attributes["xrpl.node.role"] != "" and attributes["xrpl.work.item"] != nil and attributes["xrpl.work.item"] != ""
-          - set(attributes["resource_group"], Concat(["[", attributes["service.instance.id"], "]"], "")) where attributes["service.instance.id"] != nil and attributes["service.instance.id"] != ""
-          - set(attributes["resource_group"], Concat(["[", attributes["service.instance.id"], ", ", attributes["xrpl.network.type"], "]"], "")) where attributes["service.instance.id"] != nil and attributes["service.instance.id"] != "" and attributes["xrpl.network.type"] != nil and attributes["xrpl.network.type"] != ""
 
 connectors:
   spanmetrics:
@@ -252,19 +224,12 @@ service:
     # the transform both writing a service_instance_id label on the same series.
     metrics/local:
       receivers: [otlp, spanmetrics]
-      processors:
-        [resource/tier, resource/stripsdk, transform/legendgroups, batch]
+      processors: [resource/tier, resource/stripsdk, batch]
       exporters: [prometheus]
     metrics/cloud:
       receivers: [otlp, spanmetrics]
       processors:
-        [
-          resource/tier,
-          resource/stripsdk,
-          transform/legendgroups,
-          transform/cloudlabels,
-          batch,
-        ]
+        [resource/tier, resource/stripsdk, transform/cloudlabels, batch]
       exporters: [otlphttp/grafanacloud]
     logs:
       receivers: [filelog]