Cardano Updates

`NoThunks` instances are used for memory leak detection during development,
but predicate failures should never be retained in the ledger state - they
are only used for validation results. Removing these instances reduces
code maintenance burden and instance derivation overhead.

This change removes `NoThunks` instances from:

- All predicate failure types across Shelley, Allegra, Alonzo, Babbage,
  Conway, and Dijkstra eras
- All predicate failures in cardano-protocol-tpraos
- All `ContextError` types (`AlonzoContextError`, `BabbageContextError`,
  `ConwayContextError`, `DijkstraContextError`)
- The `NoThunks (ContextError era)` constraint from the `EraPlutusContext` class
- The `NoThunks` deriving instance for `CollectError`

`NoThunks` instances are used for memory leak detection during development,
but predicate failures should never be retained in the ledger state - they
are only used for validation results. Removing these instances reduces
code maintenance burden and instance derivation overhead.

This change removes `NoThunks` instances from:

- All predicate failure types across Shelley, Allegra, Alonzo, Babbage,
  Conway, and Dijkstra eras
- All `ContextError` types (`AlonzoContextError`, `BabbageContextError`,
  `ConwayContextError`, `DijkstraContextError`)
- The `NoThunks (ContextError era)` constraint from the `EraPlutusContext` class
- The `NoThunks` deriving instance for `CollectError`

`validateInputSetEmptyUTxO`, `validateBadInputsUTxO`,
`validateMaxTxSizeUTxO`, `validateOutputBootAddrAttrsTooBig``

Refactor such that each example from an era is build on top of the
example of the previous era.

Allows:
* reduced duplication
* each example of each era has most fields set with values

Forecast t BabbageEra = BabbageForecast t BabbageEra

* Add ./script/nix-format.sh for non-Nix users.
* Add nixfmt in our Nix pre-commit hook.
* Add Github CI check

The metadatum decoder now only enforces bytes/text size limits (0..64)
for decoder versions > 2, matching the previous SoftForks.validMetadata
behavior. Tests are added to roundTripShelleyCommonSpec so they run for
every era: accepting oversized values at version 2 (Shelley) and
rejecting them from version 3 (Allegra) onwards.

Changes made with the help of an LLM

The CDDL spec requires `bytes .size (0..64)` and `text .size (0..64)`
for transaction metadatum, but the decoder did not enforce these limits.
This moves the size validation into `decodeMetadatum` so it aligns with
the CDDL spec. The `Arbitrary Metadatum` instance is also constrained
to produce valid values, and the previously disabled CDDL anti-tests
are now enabled.

Changes made with the help of an LLM

Forecast t BabbageEra = BabbageForecast t BabbageEra

Migrate scripts to `cardano-ledger-release-tool`

The metadatum decoder now only enforces bytes/text size limits (0..64)
for decoder versions > 2, matching the previous SoftForks.validMetadata
behavior. Tests are added to roundTripShelleyCommonSpec so they run for
every era: accepting oversized values at version 2 (Shelley) and
rejecting them from version 3 (Allegra) onwards.

Changes made with the help of an LLM

Enable Shelley anti-tests for update, proposed_protocol_parameter_updates,
protocol_param_update, and certificate. Enable Dijkstra transaction
arbitrary validate test that previously hung. Remaining xdescribes are
for unrelated issues.

Changes made with the help of an LLM