Feature: Add Onramp/Offramp Service(s)

[kamescg]

Context

The Universal stack doesn't currently include any onramp or offramp services.

During the early alpha we expect users to add funds from an existing onchain wallet, but long-term users should be able to easily purchase stablecoins and other "blue chip" tokens in the application(s).

Scope

Add an on-ramping and off-ramping service(s) to the apps/wallet and apps/popup applications.

Top Options:

• Coinbase
• Stripe
• Moonpay
• Robinhood