[ADP-3350] Conversion to/from `Read.ChainPoint`

[HeinrichApfelmus]

This pull request adds conversion function to/from the data type ChainPoint that belongs to the Cardano.Wallet.Read hierarchy.

This includes

• Conversions to/from legacy types in primitive
• Conversions to/from types in ouroboros-consensus for the networking layer

Comments

• The goal is to eventually remove the old primitive types. However, we add conversions Read.ChainPoint ⟷ ChainPoint here in order to have more control over the source code impact of future pull requests. Specifically, we can then change the types in NetworkLayer from ChainPoint to Read.ChainPoint while touching only a small portion of the code in Cardano.Wallet thanks to a cleverly inserted conversion.

Issue Number

ADP-3350

[HeinrichApfelmus]

Thanks for the review! 🙏

Some food for thought ... Should we at some point in future think about adding roundtrips checking

Ah. Fair enough. I consider this particular code to be "obviously correct", and the type checker imposes strong constraints on what it can do, but there is always undefined or typos. Testing the roundtrip ouroboros-consensus ⟷ ChainPoint may be a sensible idea, whereas I would skip it for the Read.ChainPoint ⟷ ChainPoint as it involves a legacy type.