add scrollIntoView command

packages/core/src/commands/scrollIntoView.ts

@@ -0,0 +1,15 @@
+import { Command } from '../Editor'
+
+type ScrollIntoViewCommand = () => Command
+
+declare module '../Editor' {
+  interface Commands {
+    scrollIntoView: ScrollIntoViewCommand,
+  }
+}
+
+export const scrollIntoView: ScrollIntoViewCommand = () => ({ tr }) => {
+  tr.scrollIntoView()
+
+  return true
+}