Split compatible transaction building and signing

[carbolymer]

Changelog

- description: |
    Split compatible transaction building into separate building and signing functions
# uncomment types applicable to the change:
  type:
  # - feature        # introduces a new feature
   - breaking       # the API has changed in a breaking way
  # - compatible     # the API has changed but is non-breaking
  # - optimisation   # measurable performance improvements
  # - refactoring    # QoL changes
  # - bugfix         # fixes a defect
  # - test           # fixes/modifies tests
  # - maintenance    # not directly related to the code
  # - release        # related to a new release preparation
  # - documentation  # change in code docs, haddocks...

Context

createCompatibleSignedTx wasn't really signing the transaction but just blindly adding signatures. It's split into two separate functions for building and signing.

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• New tests are added if needed and existing tests are updated. See Running tests for more details
• Self-reviewed the diff

[carbolymer]

I'ts a 1-1 copy from Cardano.Api.Internal.Tx.Sign. I imagine that we'll be deprecating eras and simplifying Cardano.Api.Internal.Tx.Sign so we won't be able to reuse code easily.

[Jimbo4350]

This will sit in a separate command group in cardano-cli. We need access to all the eras, so we won't be deprecating any eras. Remember QA has a hardforking test where they submit protocol parameter updates across all eras.

[carbolymer]

We need access to all the eras, so we won't be deprecating any eras.

But we will be supporting only current and next eras so only Cardano.Api.Internal.Compatible will support older eras, right?

[Jimbo4350]

Cardano.Api.Internal.Compatible has to support all Shelley based eras only for the functionality QA needs.

Once we can provide what QA needs, we can consider parameterizing functions in Cardano.Api.Internal.Compatible on CardanoEra era however the Byron/Shelley split in the code makes things cleaner.

[Jimbo4350]

We want to eventually remove ShelleyTxBody so lets not do this.

[carbolymer]

Ok I'll try to rewrite this without using our TxBody type