Cardano Updates

Use Gen.shuffle to vary cert ordering across runs, giving meaningful
random variation now that the test covers multiple cert types with
both Nothing and Just witnesses.

Extract shared indexCertificatesWith helper that preserves certificates
with Nothing witnesses (non-witnessed certs like ConwayRegCert without
deposit). Previously, all three indexTxCertificates implementations
filtered out Nothing-witness certs, causing mapScriptWitnessesCertificates
in both the legacy and experimental APIs to silently drop them during
fee balancing.

Also replaces the inlined cert-indexing in the experimental API's
mapScriptWitnessesCertificates with a call to indexTxCertificates,
and expands the cert-preservation property test to cover delegation
and registration+delegation cert types.

Fixes #1138

  DecommitFinalized aggregate now resets seenSnapshot to
  LastSeenSnapshot{confirmedSn} instead of toLastSeenSnapshot(seenSnapshot).
  This prevents seenSnapshotNumber from advancing to the requested snapshot
  number (which blocked re-requesting), and allows onOpenChainDecrementTx
  to emit a fresh ReqSn with the new version for any pending L2 txs.

Signed-off-by: Sasha Bogicevic <[email protected]>

  After a decommit snapshot confirms, the leader immediately requests the
  next snapshot via maybeRequestNextSnapshot, sending ReqSn(ver=N). If
  DecommitFinalized arrives before the network echo returns, it bumps the
  version to N+1, causing the stale ReqSn(ver=N) echo to be rejected with
  ReqSvNumberInvalid. Since nothing re-triggers a fresh request, the head
  gets permanently stuck in RequestedSnapshot.

Signed-off-by: Sasha Bogicevic <[email protected]>

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

Signed-off-by: Allain Magyar <[email protected]>

Signed-off-by: William Hankins <[email protected]>

feat: upgrade DMQ node to `0.3.0.0-pre`

Pay down test coverage debt for Flat serialization instances.
This ensures encoding stability is verified by tests before
we attempt to fix the Generic derivation bug in a follow-up PR.

Adds roundtrip and stable byte encoding tests for:
- Flat library types (Maybe, Either, NonEmpty, Complex, Ratio,
  Set, Tree, Map, Seq, DList, Filler, PreAligned, and
  monoid/semigroup wrappers)
- TPLC types (Version, Name, Kind, DeBruijn, NamedDeBruijn,
  SrcSpan, SrcSpans, DefaultFun, DefaultUni, and all newtype
  wrappers including TyName, Unique, TyDeBruijn, etc.)
- PIR types (Recursivity, Strictness)
- UPLC types (Binder variants, FakeNamedDeBruijn, minimal
  Program encoding)
- Value types (K encodes as ByteString, Quantity as Integer)

Also adds a standalone encoding generator executable
(cabal run flat-encoding-generator) for reproducing expected
byte constants.

refactor(scripts): streamline jq usage and temp file handling