[Feature request] Keysend push funds to peer channel

[Darth-Coin]

Use case scenario:

• small merchant use SBW to receive payments
• merchant open a channel with a customer that have a LN node
• merchant will have to push all the funds on the peer side (customer) in order to be able to receive payments from this customer in the future
• a keysend push button will be easy way to do that
• customer send the funds to SBW onchain address, merchant use those funds to open the channel towards customer node and push the funds to remote side (customer get back the sats)
• once the channel is empty on SBW side, customer can start paying from that channel the merchant

Another option will be to be able for the customer to open a channel towards SBW wallet node ID, but right now this is not possible and not sure how can be done, will need a tor address for SBW wallet.