feat: error connections

frontend/src/app/canvas/CanvasPage.tsx

@@ -274,6 +274,7 @@ export function CanvasPage({ projectId }: CanvasPageProps) {
   const pathUpdateEndTimeoutRef = useRef<ReturnType<typeof setTimeout> | null>(null)
 
   const [connectionPathPausedNodeIds, setConnectionPathPausedNodeIds] = React.useState<string[]>([])
+  const [connectionPathErrorNodeIds, setConnectionPathErrorNodeIds] = React.useState<string[]>([])
   const connectionPathPausedNodeIdsRef = useRef<string[]>([])
   connectionPathPausedNodeIdsRef.current = connectionPathPausedNodeIds
 
@@ -586,6 +587,14 @@ export function CanvasPage({ projectId }: CanvasPageProps) {
     setConnectionPathPausedNodeIds((prev) => prev.filter((id) => id !== nodeId))
   }, [])
 
+  const addConnectionPathError = useCallback((nodeId: string) => {
+    setConnectionPathErrorNodeIds((prev) => (prev.includes(nodeId) ? prev : [...prev, nodeId]))
+  }, [])
+
+  const removeConnectionPathError = useCallback((nodeId: string) => {
+    setConnectionPathErrorNodeIds((prev) => prev.filter((id) => id !== nodeId))
+  }, [])
+
   const flowContextValue = useMemo(
     () => ({
       nodes,
@@ -609,6 +618,9 @@ export function CanvasPage({ projectId }: CanvasPageProps) {
       connectionPathPausedNodeIds,
       addConnectionPathPausedNode,
       removeConnectionPathPausedNode,
+      connectionPathErrorNodeIds,
+      addConnectionPathError,
+      removeConnectionPathError,
       startConnectionPathUpdate,
       endConnectionPathUpdate,
     }),
@@ -634,6 +646,9 @@ export function CanvasPage({ projectId }: CanvasPageProps) {
       connectionPathPausedNodeIds,
       addConnectionPathPausedNode,
       removeConnectionPathPausedNode,
+      connectionPathErrorNodeIds,
+      addConnectionPathError,
+      removeConnectionPathError,
       startConnectionPathUpdate,
       endConnectionPathUpdate,
     ]