Add lnwallet commands to extract root priv key

[Kukks]

No description provided.

[Kukks]

usage on btcpay:
make sure lnd is not running in image (i modified my docker-entrypoint to test )
docker exec -ti btcpayserver_lnd_bitcoin lnwallet walletinfo --with_root_key --wallet_file /root/.lnd/data/chain/bitcoin/mainnet/wallet.db

[NicolasDorier]

What does it extract exatcly?

[Kukks]

It is this: lightningnetwork#2373

There are those 2 files I sent you in DM
Essentially, it lets you export:

• a bitcoind compatible wallet file with all the private keys & addresses
• the BIP32 extended root key

With these commands users can recover their funds without needing to do all the crazy genesis rescans on lnd. Maybe we can even figure out a way to transition users from noseedbackup with this