Add localisation

[danirukun]

Use something like https://crowdin.com

We will implement a few top languages used by Hololive fans first.
Since we are using Svelte let's try to use something like https://github.com/kaisermann/svelte-i18n

[CenTdemeern1]

I have good experiences with Crowdin from working with osu!, seems like a nice option

[danirukun]

@VTGare would you like to help out with UA localisation later?

[VTGare]

@VTGare would you like to help out with UA localisation later?

Yes sure! I can translate it to Russian and Ukrainian