Replace closed-range eon eliminators with forEraInEon in cardano-cli

[Jimbo4350]

Context

Part of removing eon witnesses from cardano-cli in favour of ShelleyBasedEra era / the experimental Era era.

This PR rewrites the four cardano-cli call sites of the closed-range eon eliminators to use forEraInEon on the CardanoEra, keyed on the surviving *EraOnwards eon:

site	was	now
Compatible/Transaction/TxOut.hs toTxOutValueInShelleyBasedEra	caseShelleyToAllegraOrMaryEraOnwards	forEraInEon (MaryEraOnwards)
EraBased/Query/Run.hs printableDatum	caseShelleyToAlonzoOrBabbageEraOnwards	forEraInEon (BabbageEraOnwards)
Compatible/Transaction/Option.hs pTxOutDatum	caseShelleyToMaryOrAlonzoEraOnwards	forEraInEon (AlonzoEraOnwards)
EraBased/Governance/Actions/Option.hs pCostModelsFile	caseShelleyToMaryOrAlonzoEraOnwards	forEraInEon (AlonzoEraOnwards)

This removes the last cardano-cli uses of ShelleyToAllegraEra, ShelleyToAlonzoEra and ShelleyToMaryEra, which unblocks deleting those (consumerless) eons from cardano-api.

How to trust this PR

Behaviour is unchanged at every site — forEraInEon's negative branch fires for exactly the same sub-cutoff eras the caseShelleyToXOr… lower branch did.

Two non-obvious details worth a reviewer's eye:

• toTxOutValueInShelleyBasedEra: the old lower branch relied on the ShelleyToAllegraEra witness to refine L.Value (ShelleyLedgerEra era) ~ Coin. forEraInEon's negative branch has no such evidence, so TxOutValueShelleyBased sbe l no longer typechecks — replaced with lovelaceToTxOutValue sbe l, which injects the coin under shelleyBasedEraConstraints.
• toTxOutValueInShelleyBasedEra positive branch: the case… eliminator brought its handler's constraints into scope automatically; forEraInEon does not, so the MaryEraOnwards body now needs an explicit maryEraOnwardsConstraints w $ ….

Verified with cabal build cardano-cli -j4 (lib, exe, and golden tests compile and link).

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• New tests are added if needed and existing tests are updated
• Self-reviewed the diff
• Changelog fragment added in .changes/