feat: introduce trigger functionality (#27644)

Signed-off-by: lyzno1 <yuanyouhuilyz@gmail.com>
Co-authored-by: Stream <Stream_2@qq.com>
Co-authored-by: lyzno1 <92089059+lyzno1@users.noreply.github.com>
Co-authored-by: zhsama <torvalds@linux.do>
Co-authored-by: Harry <xh001x@hotmail.com>
Co-authored-by: lyzno1 <yuanyouhuilyz@gmail.com>
Co-authored-by: yessenia <yessenia.contact@gmail.com>
Co-authored-by: hjlarry <hjlarry@163.com>
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web/app/components/workflow/nodes/start/default.ts

@@ -7,10 +7,10 @@ const metaData = genNodeMetaData({
   sort: 0.1,
   type: BlockEnum.Start,
   isStart: true,
-  isRequired: true,
-  isUndeletable: true,
+  isRequired: false,
   isSingleton: true,
-  isTypeFixed: true,
+  isTypeFixed: false, // support node type change for start node(user input)
+  helpLinkUri: 'user-input',
 })
 const nodeDefault: NodeDefault<StartNodeType> = {
   metaData,