Cardano Updates

This was missed by: #5111

Co-authored-by: Onyinyechi46 <[email protected]>

Currently, the `B` constructor contains a `ByteString` (pinned in
memory) with a max length of 64 bytes. Since the `ByteString` is small
and can be instantiated frequently, it makes more sense to use an
unpinned bytestring representation (`ShortByteString` which has
underlying type `ByteArray`) so that we can take advantage of Haskell's
garbage collection to improve memory allocation of objects in the heap.

Add withGenerator to plutus_v4_script to prevent set collisions, matching
the fix for V1/V2/V3. Enable previously disabled Dijkstra tests that now
pass: AuxData roundtrip, TxOut/Script/TxWits ArbitraryValidate,
PParamsUpdate/ProposalProcedure/GovAction ArbitraryValidate, and TxAuxData
decoder equivalence. Update xdescribe reasons for tests that remain
disabled (plutus_v4_script tag 4 not yet supported by decoder, metadatum
validation, empty redeemers).

Co-Authored-By: Claude Opus 4.6 <[email protected]>

Implement custom `ToExpr` instance for `Mismatch` datatype.

After removing distinct_bytes, the CDDL generator could produce
duplicate empty byte strings for plutus scripts in nonempty_set
collections (tag 258). The Set decoder would deduplicate them,
causing a length mismatch error. Fix by generating 32-byte random
bytestrings which makes collisions virtually impossible.

Also mark proposal_procedure antiCborSpec as pending due to
unrelated protver decoder issue.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

This was missed by: #5111

Co-authored-by: Onyinyechi46 <[email protected]>

This was missed by: #5111

Co-authored-by: Onyinyechi46 <[email protected]>

We do should *not* provide a default implementation for 'fromPlutusData'
because types should always be invertible from 'PlutusData'. Therefore,
we force the user to make a conscious decision to not provide an
implementation for this function.

The `Show` instance for Mismatch was modified to show type level information.
The same thing needs to be done for the `TreeDiff` instance.

Example of the `Expr`:

```
ghci> toExpr (Mismatch @RelEQ (42 :: Int) 100)
Rec "Mismatch (RelEQ)" (fromList [("supplied",App "42" []),("expected",App "100" [])])
```

Remove redundant UTXO predicate failures