refactor(skill): unify root/blank constants and eliminate magic strings

- Add constants.ts with ROOT_ID, CONTEXT_MENU_TYPE, NODE_MENU_TYPE
- Add root utilities to tree-utils.ts (isRootId, toApiParentId, etc.)
- Replace '__root__' with ROOT_ID for consistent root identifier
- Replace inline 'blank'/'root' strings with constants
- Use NodeMenuType for type-safe menu type props
- Remove duplicate ContextMenuType from types.ts, use from constants.ts

web/app/components/workflow/skill/file-tree/index.tsx

@@ -13,6 +13,7 @@ import { useTranslation } from 'react-i18next'
 import Loading from '@/app/components/base/loading'
 import { useStore, useWorkflowStore } from '@/app/components/workflow/store'
 import { cn } from '@/utils/classnames'
+import { CONTEXT_MENU_TYPE, ROOT_ID } from '../constants'
 import { useInlineCreateNode } from '../hooks/use-inline-create-node'
 import { useRootFileDrop } from '../hooks/use-root-file-drop'
 import { useSkillAssetTreeData } from '../hooks/use-skill-asset-tree'
@@ -63,7 +64,7 @@ const FileTree: React.FC<FileTreeProps> = ({ className, searchTerm = '' }) => {
   const storeApi = useWorkflowStore()
 
   // Root dropzone highlight (when dragging to root, not to a specific folder)
-  const isRootDropzone = dragOverFolderId === '__root__'
+  const isRootDropzone = dragOverFolderId === ROOT_ID
 
   useEffect(() => {
     if (!dragOverFolderId)
@@ -114,7 +115,7 @@ const FileTree: React.FC<FileTreeProps> = ({ className, searchTerm = '' }) => {
     storeApi.getState().setContextMenu({
       top: e.clientY,
       left: e.clientX,
-      type: 'blank',
+      type: CONTEXT_MENU_TYPE.BLANK,
     })
   }, [storeApi])
 

web/app/components/workflow/skill/file-tree/node-menu.tsx

@@ -2,6 +2,7 @@
 
 import type { FC } from 'react'
 import type { NodeApi, TreeApi } from 'react-arborist'
+import type { NodeMenuType } from '../constants'
 import type { TreeNodeData } from '../type'
 import {
   RiDeleteBinLine,
@@ -15,6 +16,7 @@ import * as React from 'react'
 import { useTranslation } from 'react-i18next'
 import Confirm from '@/app/components/base/confirm'
 import { cn } from '@/utils/classnames'
+import { NODE_MENU_TYPE } from '../constants'
 import { useFileOperations } from '../hooks/use-file-operations'
 import MenuItem from './menu-item'
 
@@ -24,7 +26,7 @@ export const MENU_CONTAINER_STYLES = [
 ] as const
 
 type NodeMenuProps = {
-  type: 'file' | 'folder' | 'root'
+  type: NodeMenuType
   nodeId?: string
   onClose: () => void
   className?: string
@@ -41,8 +43,8 @@ const NodeMenu: FC<NodeMenuProps> = ({
   node,
 }) => {
   const { t } = useTranslation('workflow')
-  const isRoot = type === 'root'
-  const isFolder = type === 'folder' || isRoot
+  const isRoot = type === NODE_MENU_TYPE.ROOT
+  const isFolder = type === NODE_MENU_TYPE.FOLDER || isRoot
 
   const {
     fileInputRef,

web/app/components/workflow/skill/file-tree/tree-context-menu.tsx

@@ -7,18 +7,13 @@ import { useClickAway } from 'ahooks'
 import * as React from 'react'
 import { useCallback, useRef } from 'react'
 import { useStore, useWorkflowStore } from '@/app/components/workflow/store'
+import { getMenuNodeId, getNodeMenuType } from '../utils/tree-utils'
 import NodeMenu from './node-menu'
 
 type TreeContextMenuProps = {
   treeRef: React.RefObject<TreeApi<TreeNodeData> | null>
 }
 
-function getMenuType(contextMenu: { type: string, isFolder?: boolean }): 'root' | 'folder' | 'file' {
-  if (contextMenu.type === 'blank')
-    return 'root'
-  return contextMenu.isFolder ? 'folder' : 'file'
-}
-
 const TreeContextMenu: FC<TreeContextMenuProps> = ({ treeRef }) => {
   const ref = useRef<HTMLDivElement>(null)
   const contextMenu = useStore(s => s.contextMenu)
@@ -45,8 +40,8 @@ const TreeContextMenu: FC<TreeContextMenuProps> = ({ treeRef }) => {
       }}
     >
       <NodeMenu
-        type={getMenuType(contextMenu)}
-        nodeId={contextMenu.type === 'blank' ? 'root' : contextMenu.nodeId}
+        type={getNodeMenuType(contextMenu.type, contextMenu.isFolder)}
+        nodeId={getMenuNodeId(contextMenu.type, contextMenu.nodeId)}
         onClose={handleClose}
         treeRef={treeRef}
       />