fix(telemetry): bake legend brackets into cloud + Alloy collector labels

Mirror the local collector change on the Grafana Cloud collector config and the
in-repo Alloy config: build the group-label VALUES with brackets and comma
separators (resource_group="[node, mainnet]",
iac_group="[branch, role, work-item]") in both trace and metric resource
statements, so span-derived and native metrics carry the same bracketed values.

This lets the dashboards use a bracket-free Display name and avoids the empty
"[]" that a templated bracket would leave when a group is absent (Grafana's
renameByRegex runs pre-interpolation and cannot strip it). Separator changes
from "-" to ", ".

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

docker/telemetry/alloy/config.alloy

@@ -157,9 +157,9 @@ otelcol.processor.transform "tier" {
       // 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"], attributes["service.instance.id"]) where attributes["service.instance.id"] != nil and attributes["service.instance.id"] != ""`,
-      `set(attributes["resource_group"], Concat([attributes["resource_group"], attributes["xrpl.network.type"]], "-")) where attributes["resource_group"] != nil and attributes["xrpl.network.type"] != nil and attributes["xrpl.network.type"] != ""`,
-      `set(attributes["iac_group"], 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"] != ""`,
+      `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"] != ""`,
     ]
   }
 
@@ -181,9 +181,9 @@ otelcol.processor.transform "tier" {
       //     it is built only on perf-comparison nodes. The guard checks != ""
       //     as well as != nil because OTTL Concat emits a stray separator for an
       //     empty element.
-      `set(attributes["resource_group"], attributes["service.instance.id"]) where attributes["service.instance.id"] != nil and attributes["service.instance.id"] != ""`,
-      `set(attributes["resource_group"], Concat([attributes["resource_group"], attributes["xrpl.network.type"]], "-")) where attributes["resource_group"] != nil and attributes["xrpl.network.type"] != nil and attributes["xrpl.network.type"] != ""`,
-      `set(attributes["iac_group"], 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"] != ""`,
+      `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

@@ -130,25 +130,27 @@ processors:
           - 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 instead of a per-panel
-  # renameByRegex chain. On the local scrape these resource attributes are
-  # promoted to labels by resource_to_telemetry_conversion; on the Cloud path
+  # 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.
-  #   - iac_group: perf-iac branch/role/work-item, stamped together (all or
-  #     none), so one guard covers them. Unset outside perf runs -> the legend
-  #     shows nothing for it.
-  #   - resource_group: node id, optionally suffixed with network type.
-  # Concat is guarded on presence (!= nil and != "") because OTTL Concat renders
-  # "<nil>" for an absent attribute and a stray separator for an empty one. The
-  # perf-iac collector stamps these with an empty-string default when a run has
-  # no work item, so the empty-string check matters, not just the nil check.
+  # 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([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"], attributes["service.instance.id"]) where attributes["service.instance.id"] != nil and attributes["service.instance.id"] != ""
-          - set(attributes["resource_group"], Concat([attributes["resource_group"], attributes["xrpl.network.type"]], "-")) where attributes["resource_group"] != nil 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"] != ""
+          - 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: