refactor: rename group/groupName to application/applicationName

The execution-related "group" concept actually represents the
application name. Rename all Java fields, API parameters, and frontend
types from groupName→applicationName and group→application for clarity.

- Java records: ExecutionSummary, ExecutionDetail, ExecutionDocument,
  ExecutionRecord, ProcessorRecord
- API params: SearchRequest.group→application, SearchController
  @RequestParam group→application
- Services: IngestionService, DetailService, SearchIndexer, StatsStore
- Frontend: schema.d.ts, Dashboard, ExchangeDetail, RouteDetail,
  executions query hooks

Database column names (group_name) and OpenSearch field names are
unchanged — only the API-facing Java/TS field names are renamed.

RBAC group references (groups table, GroupRepository, GroupsTab) are
a separate domain concept and are NOT affected by this change.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/src/api/queries/executions.ts

@@ -6,10 +6,10 @@ export function useExecutionStats(
   timeFrom: string | undefined,
   timeTo: string | undefined,
   routeId?: string,
-  group?: string,
+  application?: string,
 ) {
   return useQuery({
-    queryKey: ['executions', 'stats', timeFrom, timeTo, routeId, group],
+    queryKey: ['executions', 'stats', timeFrom, timeTo, routeId, application],
     queryFn: async () => {
       const { data, error } = await api.GET('/search/stats', {
         params: {
@@ -17,7 +17,7 @@ export function useExecutionStats(
             from: timeFrom!,
             to: timeTo || undefined,
             routeId: routeId || undefined,
-            group: group || undefined,
+            application: application || undefined,
           },
         },
       });
@@ -49,10 +49,10 @@ export function useStatsTimeseries(
   timeFrom: string | undefined,
   timeTo: string | undefined,
   routeId?: string,
-  group?: string,
+  application?: string,
 ) {
   return useQuery({
-    queryKey: ['executions', 'timeseries', timeFrom, timeTo, routeId, group],
+    queryKey: ['executions', 'timeseries', timeFrom, timeTo, routeId, application],
     queryFn: async () => {
       const { data, error } = await api.GET('/search/stats/timeseries', {
         params: {
@@ -61,7 +61,7 @@ export function useStatsTimeseries(
             to: timeTo || undefined,
             buckets: 24,
             routeId: routeId || undefined,
-            group: group || undefined,
+            application: application || undefined,
           },
         },
       });