feat: resolved URI display and drill-down for TO/TO_DYNAMIC nodes

- Show resolved endpoint URI as teal italic line on diagram nodes
  when execution overlay is active
- Enable drill-down for TO and TO_DYNAMIC nodes (not just DIRECT/SEDA)
- Use runtime resolvedEndpointUri from execution overlay for drill-down
  when static endpointUri doesn't match
- Increase node height from 50px to 56px to accommodate the third line

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

ui/src/components/ExecutionDiagram/types.ts

@@ -10,6 +10,8 @@ export interface NodeExecutionState {
   subRouteFailed?: boolean;
   /** True if trace data is available for this processor */
   hasTraceData?: boolean;
+  /** Runtime-resolved endpoint URI (for TO_DYNAMIC, etc.) */
+  resolvedEndpointUri?: string;
 }
 
 export interface IterationInfo {

ui/src/components/ExecutionDiagram/useExecutionOverlay.ts

@@ -60,6 +60,7 @@ function buildOverlay(
       durationMs: proc.durationMs ?? 0,
       subRouteFailed: subRouteFailed || undefined,
       hasTraceData: !!proc.hasTraceData,
+      resolvedEndpointUri: proc.resolvedEndpointUri || undefined,
     });
 
     // Recurse into children