Using `umami-api` instead of rebuilding an API client

[imjuniper]

Hey there! I made a Node API client for Umami (still quite WIP), and I was thinking since it already has basically all of the website-related functions done, it could be a good starting point for the CLI.

GitHub and NPM links.

[imjuniper]

I now have all the available endpoints programmed in! There are probably some adjustments to make for it to be compatible with a CLI environment, but I'd be happy to help!

[imjuniper]

Kinda related to this, how much time are the tokens valid for? I could add a way to create a client with a token only, if they're valid for long enough. Unless you are planning on adding API keys/access tokens instead.