[lisicky]

What

Adds part builders for every certificate the Conway ledger accepts. Also makes the TransactionPrototype encoder keep the deposit of Conway stake (de)registration certificates instead of dropping it.

Stacked on #855. Merge it first; this PR can then be retargeted to main. The part builders stay in packages/mesh-transaction/src/tx-builder/, not exported from the package root.

Contents

packages/mesh-transaction/src/tx-builder/parts/certificates.ts, one builder per CDDL certificate:

Builder	Certificate
stakeRegistration, stakeDeregistration	7, 8: Conway, deposit stated
legacyStakeRegistration, legacyStakeDeregistration	0, 1
stakeDelegation	2
poolRegistration, poolRetirement	3, 4
voteDelegation, stakeAndVoteDelegation	9, 10
stakeRegistrationAndDelegation, voteRegistrationAndDelegation, stakeVoteRegistrationAndDelegation	11, 12, 13
committeeHotAuth, committeeColdResign	14, 15
drepRegistration, drepDeregistration, drepUpdate	16, 17, 18

• Credentials, pools and DReps:
  • Stake and committee credentials are given as a bech32 reward address or as the credential itself.
  • DReps as a CIP-105/CIP-129 id, a credential, a DRepPrototype, "alwaysAbstain" or "alwaysNoConfidence".
  • Pools as a bech32 id or a key hash.
  • poolRegistration takes Mesh PoolParams. Margin, pledge and cost, VRF and owner hashes, the reward address, relays (IPv4, IPv6 with ::, DNS names, ports) and metadata are all checked.
• Witnesses:
  • A key credential takes no witness argument.
  • A script credential needs witness: { native } or { plutus, redeemer }, checked against the credential's hash. A script referenced by out ref alone gets its hash from the credential.
  • Certificates introduced with governance can only be witnessed by a Plutus V3 script. The legacy deregistration and stake delegation accept any version.
  • The legacy stake registration takes no witness; pool certificates are signed by the keys they name.
• Deposits and refunds. They can be given explicitly. When omitted, the part records the protocol parameter they come from (keyDeposit, drepDeposit), and unresolved reports it as a deposit gap.
• Order. Certificates keep the order their parts are given in, as that order is part of the transaction.

mesh-core-cst:

• Encoder fix. certificatePrototypeToCardano now encodes STAKE_REGISTRATION / STAKE_DEREGISTRATION with a coin as certificates 7/8, Registration / Unregistration with the deposit. Without a coin, the legacy 0/1 are produced as before. Previously the deposit was silently dropped, so these certificates did not round-trip.
• The round-trip test that pinned the loss now checks both forms survive. The decoder comment and docs/design/tx-prototype.md are updated.

Validation

npm run build:mesh
cd packages/mesh-transaction && npx jest test/tx-builder
cd packages/mesh-core-cst && npm test

• 16 new tests in certificates.test.ts:
  • every builder;
  • witness and Plutus V3 rules;
  • deposit gaps;
  • malformed pool parameters, anchors, ids and DReps;
  • a round trip of all 16 certificate forms through transactionPrototypeToHex / transactionPrototypeFromHex.
• mesh-core-cst: 180 tests pass.
• mesh-transaction (NODE_OPTIONS=--experimental-vm-modules npx jest): 224 tests pass. script-tx-fetcher and script-tx-fail fail to load under that flag on main too.