[chore]: use wrapper structs for heights

[MCJOHN974]

Description

WIP

Closes: #1405

Changes

Scope: refactoring was only in signer
New dep: it is actually my code I wrote for this task, just was thinking for a while it can be useful to have it as a separate lib, with ability to reuse in other projects. However, I'm not sure if it can be useful after tried to use it (=. Anyway, if we do not want to add it as a dependency we can just move code from it to sbtc repo.

Testing Information

Since it is small refactoring we do not need any new tests.

Checklist:

• I have performed a self-review of my code
• My changes generate no new warnings
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[MCJOHN974]

Whoa, during this PR, I first started with changing all heights from u64 to my structs everywhere in code. And now I have a couple of errors saying "you try to put Stacks height but expected Bitcoin height". And this is great, this mean this aliases are really useful!

[MCJOHN974]

whoops, sqlx don't actually work =(