fix: color edges into compound nodes green when descendants were executed

Edges into/out of compound nodes (DO_TRY, EIP_CHOICE, etc.) now show as
traversed (green) when any descendant node was executed, instead of grey.

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

ui/src/components/ProcessDiagram/ProcessDiagram.tsx

@@ -81,18 +81,44 @@ export function ProcessDiagram({
     application, currentRouteId, direction, effectiveLayout,
   );
 
-  // Collect ENDPOINT node IDs — these are always "traversed" when overlay is active
-  // because the endpoint is the route entry point (not in the processor execution tree).
-  const endpointNodeIds = useMemo(() => {
+  // Build a set of node IDs that should count as "traversed" for edge coloring.
+  // This includes ENDPOINT nodes (always traversed) and compound nodes where
+  // any descendant was executed (so edges into/out of DO_TRY etc. are green).
+  const traversedNodeIds = useMemo(() => {
     const ids = new Set<string>();
-    if (!overlayActive || !sections.length) return ids;
+    if (!overlayActive || !effectiveOverlay || !sections.length) return ids;
+
+    // ENDPOINTs are always traversed
     for (const section of sections) {
       for (const node of section.nodes) {
         if (node.type === 'ENDPOINT' && node.id) ids.add(node.id);
       }
     }
+
+    // Mark compound nodes as traversed if any descendant was executed
+    function hasExecutedDescendant(node: DiagramNodeType): boolean {
+      if (effectiveOverlay!.has(node.id)) return true;
+      if (node.children) {
+        for (const child of node.children) {
+          if (hasExecutedDescendant(child)) return true;
+        }
+      }
+      return false;
+    }
+    function markCompounds(nodes: DiagramNodeType[]) {
+      for (const node of nodes) {
+        if (isCompoundType(node.type) && node.children?.length && hasExecutedDescendant(node)) {
+          ids.add(node.id);
+        }
+        if (node.children) markCompounds(node.children);
+      }
+    }
+    for (const section of sections) {
+      markCompounds(section.nodes);
+    }
+
     return ids;
-  }, [overlayActive, sections]);
+  }, [overlayActive, effectiveOverlay, sections]);
 
   const zoom = useZoomPan();
   const toolbar = useToolbarHover();
@@ -299,8 +325,8 @@ export function ProcessDiagram({
           {/* Main section top-level edges (not inside compounds) */}
           <g className="edges">
             {mainSection.edges.filter(e => topLevelEdge(e, mainSection.nodes)).map((edge, i) => {
-              const sourceHasState = effectiveOverlay?.has(edge.sourceId) || endpointNodeIds.has(edge.sourceId);
-              const targetHasState = effectiveOverlay?.has(edge.targetId) || endpointNodeIds.has(edge.targetId);
+              const sourceHasState = effectiveOverlay?.has(edge.sourceId) || traversedNodeIds.has(edge.sourceId);
+              const targetHasState = effectiveOverlay?.has(edge.targetId) || traversedNodeIds.has(edge.targetId);
               const isTraversed = effectiveOverlay
                 ? (!!sourceHasState && !!targetHasState)
                 : undefined;