Cardano Updates

Signed-off-by: Akhil Repala <[email protected]>

Signed-off-by: Akhil Repala <[email protected]>

Signed-off-by: Akhil Repala <[email protected]>

by extracting the shared logic in helpers

in `mkStAnnTx`

Signed-off-by: Akhil Repala <[email protected]>

Following adjustements from the auto-derived impl re-used from serde:
- leverage `SignedEntityTypeDiscriminantMessage` to avoid defining +
  implementing deserialize on a an enum which define only the variants
  names
- use imports instead of absolute path
- rename visitors based on their implented symbol for clarity
- remove most magic strings by using `stringify!`
- use `ok_or` instead of `match` for error handling when visiting tuple
  variants

By re-using the expanded macro of serde derive.

The AsData-generated code uses head/tail and emits pattern synonyms
without signatures, tripping -Werror=x-partial and
-Werror=missing-pattern-synonym-signatures. These are inherent to the plugin
output, so suppress them on the test module (the plugin firing is confirmed by
the generated code compiling at all).

Co-Authored-By: Claude Opus 4.8 <[email protected]>

so it can be reused in Alonzo

to replace `applyTxValidation`, operating on `ValidatedTx`.
Define `applyTxValidation` in terms of `applyTxWithValidation`

for more per-era control over revalidation of transactions