This commit adds the protocol version to each stored swap. This will be
used to ensure that when swaps are resumed after a restart, they're
correctly handled given any breaking protocol changes.
Once we have revealed our preimage to the world with a sweep attempt,
we can safely push our preimage to the server to speed up on chain
claim.
Rather than rely on the server, we use the state of our invoice in lnd
to determine whether we should continue trying to push the preimage to
the server.
This allows Loop users to further improve their privacy by not revealing
their source IP address. Note that the identity of the lnd node behind
Loop can still be revealed when performing a Loop In due to the swap
server extending an off-chain HTLC to the user.
Onion addresses don't yet exist for the swap servers, but they will be
added at a later time.
We need the ability to connect to a swap server that uses
a self-signed certificate. The LSAT proxy cannot proxy insecure
gRPC requests since they don't conform to the HTTP 1.1 standard.
Therefore the LSAT proxy fill only serve TLS connections.
This means, we need the TLS path option to specify the certificate
the test environment LSAT proxy uses.
We update to new set of server protos where new Terms calls are added.
Here static information will be returned from the server.
We no longer have a feebase+feerate, but get a final fee directly
returned by the server.
