feat: introduce trigger functionality (#27644)

Signed-off-by: lyzno1 <yuanyouhuilyz@gmail.com>
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web/app/components/workflow/nodes/constants.ts

@@ -1,5 +1,7 @@
 import { TransferMethod } from '@/types/app'
 
+export const CUSTOM_NODE_TYPE = 'custom'
+
 export const FILE_TYPE_OPTIONS = [
   { value: 'image', i18nKey: 'image' },
   { value: 'document', i18nKey: 'doc' },