Wallet: remove v0 support

[callebtc]

We don't need to support v0 in wallets anymore.

[KvngMikey]

hi @callebtc @gudnuf, please can take this cleanup issue ?

[KvngMikey]

Hi @callebtc, hope you see this on time, so i started working on this issue, but I want to make sure I fully understand what’s expected before making changes I've already started up on.

From what I see, this issue is about removing support for wallet version 0, but I’m not entirely sure which parts of the codebase still depend on v0 (e.g., are there specific modules, migration logic, or API references that should be dropped?).

Could you clarify:

• Which files or features are safe to remove/update?
• Should I also clean up any related tests, configs, or documentation referencing v0?

Thanks in advance! I just want to make sure I’m aligned before I start the cleanup.

[callebtc]

Hi, I'm not on my computer right now so hard to reference files but we should remove the deprecated wallet API file and all related tests for the V0 wallet. We should keep the V0 mint around for a little bit longer too but eventually get rid of it too, once and for all!