Fix btc wallet restore

[louisinger]

This PR is a draft, waiting for btcsuite/btcwallet#957

TL;DR

• remove unused Rescan call
• first account index set to 0 ("default" name)

It fixes the restore process for the main account, but the connectors account (with index = 1) is not restored (see btcwallet issue).

[tiero]

Reason to NOT mix the connectors scripts in the same main account script? We still know which is which by database no?

[louisinger]

Reason to NOT mix the connectors scripts in the same main account script? We still know which is which by database no?

connectors must not be spent during a certain period of time so having two accounts makes the coin selection simpler.
also for ASP "analysis", I do think it makes the available liquidity clearer if we don't mix connectors and main funds.

another way to solve would be to use p2tr scope for connector instead of p2wpkh : this way the connector account index will be 0 and should be restored

[tiero]

p2tr scope

Care to elaborate here?

we don't mix connectors and main funds.

This is important, and assigning a bip44 account to each makes sense, but we could have those information in database worst case.

[louisinger]

Care to elaborate here?

Only the "default" account for each scope is restored. Today we are using the same scope for the connector and the main account (the p2wkh one). It means that one is the default account and the other a custom account. If we move one of the accounts to p2tr scope instead of p2wkh, we could use "default" for all accounts and thus make the restoration work.

TL;DR if connector account = default p2tr account, it will remove the need for custom account