Add custom Login and Register Page

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Description:

We need a custom Login and Register Page for our Users.

Info for dev:

Styling is not important at this stage, functionality comes first.

Reusable Components should go into src/components don't put them in the src/app directory or else the server will serve them standalone as well.

A quick tutorial on how to implement custom login pages: https://codevoweb.com/nextjs-use-custom-login-and-signup-pages-for-nextauth-js/

The configuration for Next-Auth can be found in: src/app/api/auth/[...nextauth]/route.ts

Documentation for Next-Auth in general can be found here: https://next-auth.js.org/

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also, check the discord channel: The .env file can be found there.