Proof of concept: Rewrite to react

[marcodejongh]

@lemeryfertitta Made a start on rewriting the FE to react so I can built #80.
Since I mostly started out spiking, there's various bits that are done that are no longer used.

I already have the abstractions ready for users to connecting to each other, but haven't started using them yet.
For the initial version, I'll add a "join session" feature, once thats used the light button is replace with something else, and that button will then change the climb through the session of the party host. I'll also show the current climb through a banner above the route selection stuff.

But selecting climbs already works, there's no filtering yet, but I'll the filtering function into the main climb screen (there's already a little search button in the screenshot).
I've also implemented collapsing and expanding of the climbs list, as an example of how easy such functionality becomes when using a FE framework.

To run it locally, the python backend needs to be ran and exposed to a public URL with ngrok, then the proxy address in package.json needs to be updated to the ngrok url. After which:

cd my-react-app
npm install
 DANGEROUSLY_DISABLE_HOST_CHECK=true HTTPS=true npm start

Will run the react app

[lemeryfertitta]

@marcodejongh glad you're psyched on this! Seems like there are some cool ideas in here.

As mentioned in #80, if you do want to contribute this back to the repo, it would really be much better to be break it down into incremental PRs. This PR is already overwhelming to look at 😅 and it seems to be far from feature parity at a glance, so I'd imagine it will be even more massive when complete.

I'm not very familiar with React. Is it possible to have part of the website running in React while we leave the majority of it unchanged, so that we can just port one page at a time? Maybe this would also allow you to work on the new feature without having to port the entirety of the app first.