[e.cash] init v2 build

Summary:
Looking to start on the new design for e.cash. Since it is an entirely new build with basically no shared design elements
I'm proposing a fresh project with the latest next.js and tailwinds for styles

Test Plan: npm i and npm run dev to see the site runs with basic e.cash setup

Reviewers: #bitcoin_abc, bytesofman

Reviewed By: #bitcoin_abc, bytesofman

Subscribers: alitayin, bytesofman

Differential Revision: https://reviews.bitcoinabc.org/D18091