Replace current iframe solution with OP

[lengyel-arpad85]

Since iframes present a problem when using session cookies and we do not control every wallet provider and how they have their sameSite cookie property setup we need a solution not using iframes.
Open Payments should be implemented, mostly copying the existing solution used by interledgerpay.com:

• initialise connection with a default wallet address, key id and private key ( we need these created on the new https://wallet.interledger-test.dev/ )
• require user wallet address and sum to pay
• generate a quote and display it for the user
• create a grant and have the user confirm / reject
• handle grant / create payment
• finalise / show success message
• reset / return user to first screen

the entire solution should be it's separate component so it can be reused in both widget and button implementation