Embed rhai playground in the router

[bnjjj]

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To improve the user experience when developing a rhai script plugin in the router, I think it could be interesting to embed the rhai playground https://github.com/rhaiscript/playground. Some thoughts:

• Having the ability to provide mocked data for each of our plugin functions
• Be able to live test a script, write a script in the playground and click on a button to hot reload the rhai script in the router