New channel on-boarding flow

[bonomat]

Figma mock can be found here:

Idea

• The user doesn't need to have funds in his on-chain wallet to get started
• When clicking through the first trade he gets confronted with a channel configurator if he doesn't have any funds
  • First he select the wanted position quantity, leverage, etc as if he would have a channel already (as known)
  • Once hits Buy (or Sell), he gets confronted with a Fund Channel-screen telling him to pick a channel size
    • The channel size can be fluent until max or with pre-defined choices
    • Once confirmed, he sees a QR code to fund the wallet
      • He can chose how to fund the wallet, either on-chain, Lightning, etc.
    • We need to wait until the transaction is at least in the mempool to continue if picked on-chain - if he cancels before, the protocol will be cancelled
    • The user continues and sends funds, after we see the tx in the mempool, we execute the protocol. The user can now leave the application safely.

Note: while it looks like it's-ready-to-implement-mock, please look on the abstract flow than on the small details.