fix: update frontend field names for identity rename (applicationId, instanceId)

The backend identity rename (applicationName → applicationId,
agentId → instanceId) was not reflected in the frontend. This caused
drilldown to fail (detail.applicationName was undefined, disabling
the diagram fetch) and various display issues.

Updated schema.d.ts, ExchangeHeader, ExecutionDiagram, Dashboard,
AgentHealth, AgentInstance, LayoutShell, LogTab, InfoTab, DetailPanel,
ExchangesPage, and tracing-store.

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

ui/src/pages/Dashboard/Dashboard.tsx

@@ -92,11 +92,11 @@ function buildBaseColumns(): Column<Row>[] {
       ),
     },
     {
-      key: 'applicationName',
+      key: 'applicationId',
       header: 'Application',
       sortable: true,
       render: (_: unknown, row: Row) => (
-        <span className={styles.appName}>{row.applicationName ?? ''}</span>
+        <span className={styles.appName}>{row.applicationId ?? ''}</span>
       ),
     },
     {
@@ -147,12 +147,12 @@ function buildBaseColumns(): Column<Row>[] {
       ),
     },
     {
-      key: 'agentId',
+      key: 'instanceId',
       header: 'Agent',
       render: (_: unknown, row: Row) => (
         <span className={styles.agentBadge}>
           <span className={styles.agentDot} />
-          {row.agentId}
+          {row.instanceId}
         </span>
       ),
     },
@@ -163,7 +163,7 @@ function buildBaseColumns(): Column<Row>[] {
 
 export interface SelectedExchange {
   executionId: string;
-  applicationName: string;
+  applicationId: string;
   routeId: string;
 }
 
@@ -226,7 +226,7 @@ export default function Dashboard({ onExchangeSelect }: DashboardProps = {}) {
     if (onExchangeSelect) {
       onExchangeSelect({
         executionId: row.executionId,
-        applicationName: row.applicationName ?? '',
+        applicationId: row.applicationId ?? '',
         routeId: row.routeId,
       })
     }