`txAuxData` does not contain scripts

There is a mismatch between `txAuxData` in the formal specification and the implementation. In the Agda specification this field is kept abstract while in the implementation it includes scrips (native scripts for Allegra, and both native and plutus scripts from Alonzo onwards).

In addition to checking that the hash for `txAuxData` matches the one provided, the implementation's UTXOW rule validates that scripts are well-formed. If they are not, the rule fails with an `InvalidMetadata` error.

Start by comparing the Agda specification's abstract txAuxData with the implementation's representation, then trace the UTXOW rule's txAuxData hash and script well-formedness checks. Review how Allegra and Alonzo handle native and Plutus scripts and how InvalidMetadata is produced. Done means the specification and implementation agree on the field contents and validation behavior.

Written by the indexing model from the issue text.