Add download button and cli command to clone example locally

[moklick]

Code of Conduct

• [x] I have read and agree to the xyflow contributor Code of Conduct

Which site are you suggesting a change for?

reactflow.dev

What content is affected by this change?

It would be nice if we could show a download button and a cli command to get started quickly with an example locally.

What part(s) of the article would you like to see updated?

examples

Additional information

No response

[moklick]

proposal:

npx create react-flow folder-name --example custom-node

or

npx create xyflow folder-name --lib react --example custom-node

[moklick]

@omesome now that we have the action bar, this could be a nice addition. wdyt?