add basic enter command

packages/core/src/commands/enter.ts

@@ -0,0 +1,36 @@
+import { Command } from '../types'
+
+/**
+ * Press Enter
+ */
+export const enter = (): Command => ({
+  editor,
+  view,
+  tr,
+  dispatch,
+}) => {
+  const keyCode = 13
+  const key = 'Enter'
+  const event = document.createEvent('Event')
+  event.initEvent('keydown', true, true)
+  // @ts-ignore
+  event.keyCode = keyCode
+  // @ts-ignore
+  event.key = key
+  // @ts-ignore
+  event.code = key
+
+  const capturedTransaction = editor.captureTransaction(() => {
+    view.someProp('handleKeyDown', f => f(view, event))
+  })
+
+  capturedTransaction?.steps.forEach(step => {
+    const newStep = step.map(tr.mapping)
+
+    if (newStep && dispatch) {
+      tr.step(newStep)
+    }
+  })
+
+  return true
+}