feat: use endpointUri for cross-route drill-down instead of label parsing

Server:
- Add endpointUri to PositionedNode (from RouteNode)
- Add fromEndpointUri to RouteSummary (catalog API)
- Catalog controller resolves endpoint URI from diagram store

UI:
- Build endpointRouteMap from catalog's fromEndpointUri field
- Drill-down uses exact match on node.endpointUri against the map
- Remove label parsing heuristics (extractTargetEndpoint, camelToKebab)

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

ui/src/pages/Exchanges/ExchangesPage.tsx

@@ -136,6 +136,21 @@ function DiagramPanel({ appId, routeId, exchangeId, onCorrelatedSelect, onClearS
     return ids;
   }, [catalog]);
 
+  // Build endpoint URI → routeId map for cross-route drill-down
+  const endpointRouteMap = useMemo(() => {
+    const map = new Map<string, string>();
+    if (catalog) {
+      for (const app of catalog as any[]) {
+        for (const r of app.routes || []) {
+          if (r.fromEndpointUri) {
+            map.set(r.fromEndpointUri, r.routeId);
+          }
+        }
+      }
+    }
+    return map;
+  }, [catalog]);
+
   // Build nodeConfigs from tracing store + app config (for TRACE/TAP badges)
   const { data: appConfig } = useApplicationConfig(appId);
   const tracedMap = useTracingStore((s) => s.tracedProcessors[appId]);
@@ -172,6 +187,7 @@ function DiagramPanel({ appId, routeId, exchangeId, onCorrelatedSelect, onClearS
           executionId={exchangeId}
           executionDetail={detail}
           knownRouteIds={knownRouteIds}
+          endpointRouteMap={endpointRouteMap}
           onNodeAction={handleNodeAction}
           nodeConfigs={nodeConfigs}
         />
@@ -187,6 +203,7 @@ function DiagramPanel({ appId, routeId, exchangeId, onCorrelatedSelect, onClearS
         routeId={routeId}
         diagramLayout={diagramQuery.data}
         knownRouteIds={knownRouteIds}
+        endpointRouteMap={endpointRouteMap}
         onNodeAction={handleNodeAction}
         nodeConfigs={nodeConfigs}
       />