refactor(telemetry): rename dashboard template variable label from 'Service' to 'Service Name'

Completes the rename applied on phase-6-statsd and phase-7-native-metrics.
These four dashboards were introduced on phase-9: peer-quality and
validator-health via b92354715d, fee-market and job-queue via 25868f2740.

Same reasoning: the underlying Prometheus label is `service_name`,
so the UI display label should say 'Service Name' rather than the
ambiguous 'Service'.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

docker/telemetry/grafana/dashboards/fee-market.json

@@ -461,7 +461,7 @@
     "list": [
       {
         "name": "service_name",
-        "label": "Service",
+        "label": "Service Name",
         "description": "Filter by service.name (e.g. xrpld, xrpld-validator)",
         "type": "query",
         "query": "label_values(service_name)",

docker/telemetry/grafana/dashboards/job-queue.json

@@ -459,7 +459,7 @@
     "list": [
       {
         "name": "service_name",
-        "label": "Service",
+        "label": "Service Name",
         "description": "Filter by service.name (e.g. xrpld, xrpld-validator)",
         "type": "query",
         "query": "label_values(service_name)",

docker/telemetry/grafana/dashboards/peer-quality.json

@@ -368,7 +368,7 @@
     "list": [
       {
         "name": "service_name",
-        "label": "Service",
+        "label": "Service Name",
         "description": "Filter by service.name (e.g. xrpld, xrpld-validator)",
         "type": "query",
         "query": "label_values(service_name)",

docker/telemetry/grafana/dashboards/validator-health.json

@@ -921,7 +921,7 @@
     "list": [
       {
         "name": "service_name",
-        "label": "Service",
+        "label": "Service Name",
         "description": "Filter by service.name (e.g. xrpld, xrpld-validator)",
         "type": "query",
         "query": "label_values(service_name)",