fix nested subflow error highlighting

Author: icecrasher321

apps/sim/app/workspace/[workspaceId]/w/[workflowId]/hooks/use-workflow-execution.ts

@@ -491,6 +491,13 @@ export function useWorkflowExecution() {
         updateActiveBlocks(data.blockId, false)
         setBlockRunStatus(data.blockId, 'error')
 
+        executedBlockIds.add(data.blockId)
+        accumulatedBlockStates.set(data.blockId, {
+          output: { error: data.error },
+          executed: true,
+          executionTime: data.durationMs || 0,
+        })
+
         accumulatedBlockLogs.push(
           createBlockLogEntry(data, { success: false, output: {}, error: data.error })
         )

apps/sim/app/workspace/[workspaceId]/w/components/preview/components/preview-workflow/preview-workflow.tsx

@@ -349,7 +349,15 @@ export function PreviewWorkflow({
       if (block.type === 'loop' || block.type === 'parallel') {
         const isSelected = selectedBlockId === blockId
         const dimensions = calculateContainerDimensions(blockId, workflowState.blocks)
-        const subflowExecutionStatus = getSubflowExecutionStatus(blockId)
+
+        // Check for direct error on the subflow block itself (e.g., loop resolution errors)
+        // before falling back to children-derived status
+        const directExecution = blockExecutionMap.get(blockId)
+        const subflowExecutionStatus: ExecutionStatus | undefined =
+          directExecution?.status === 'error'
+            ? 'error'
+            : (getSubflowExecutionStatus(blockId) ??
+              (directExecution ? (directExecution.status as ExecutionStatus) : undefined))
 
         nodeArray.push({
           id: blockId,