Cardano Updates

Adds round-trip, format, and signing tests plus a criterion benchmark
suite for the cardano-crypto-wallet package.

Adds the cardano-crypto-wallet Haskell package exposing
Cardano.Crypto.WalletHD.Encrypted, which provides authenticated
encryption and key derivation for HD wallet keys using the v2 envelope
format (Argon2id KDF + XChaCha20-Poly1305 AEAD via libsodium).

Vendors the ed25519-donna implementation and encrypted-signing C code
from the cardano-crypto package into this repository.

Adds three endpoints for surfacing constitutional committee state and votes:

- GET /governance/committee — current committee snapshot with members,
  quorum, members count, and source NewCommittee gov action (genesis
  committee returns proposal fields as null and `is_genesis: true`).
- GET /governance/committee/votes — paged list of all CC votes ever cast.
- GET /governance/committee/:cc_id/votes — paged list of votes filtered
  by CIP-129 hot (cc_hot1...) or cold (cc_cold1...) credential.
  Cold queries aggregate across every hot key the cold has authorized.

Per-vote shape includes the voting anchor (metadata_url / metadata_hash),
governance_type, block height/time, and the voter's CIP-129 hot id.

Depends on a forthcoming @blockfrost/openapi release that adds the
matching path + schema definitions.

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

- Fixtures: add `deposit` to /accounts/:stake_address response/query
  fixtures and per-row to /accounts/:stake_address/registrations
  (registered → string; deregistered → null) so route unit tests
  cover the new field per Copilot review.
- SQL: lift the `MAX(stake_registration.tx_id) > MAX(stake_deregistration.tx_id)`
  comparison into a `registration_state` CTE and reuse it from both
  the `registered` field and the deposit CASE. Eliminates a redundant
  pair of subqueries per request.

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

The chain-state prune landed in a781d1548 left `tx_arcs` and
`announced_or_known` growing forever because they carried no slot
label.  At NA,0.200 with 7.5 tx/s × 1500 slots that's >11k
unbounded entries plus the unmatched `tx_id → Arc<Transaction>`
references they pin, dominating the late-run memory growth that
still pushed RSS to 11 GB at slot 373.

`tx_seen_slot: BTreeMap<TxId, u64>` records the first-observe slot
on every entry path (`handle_new_tx`, `Message::AnnounceTx`,
`Message::Tx`).  `prune_chain_state` then ages the tx side-tables
on a second clock (sim's `linear-tx-max-age-slots`, default 100)
while preserving anything still in `MempoolState::current_tx_ids`
— mirrors `linear_leios::prune_old_txs`.

Determinism check passes (`cmp` clean on simple.yaml/300 slots).

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

Bumps [urllib3](https://github.com/urllib3/urllib3) from 2.6.3 to 2.7.0.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/main/CHANGES.rst)
- [Commits](https://github.com/urllib3/urllib3/compare/2.6.3...2.7.0)

---
updated-dependencies:
- dependency-name: urllib3
  dependency-version: 2.7.0
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>

Signed-off-by: Jonathan Lim <[email protected]>

This commit serves as an example of a pattern that we will use for all
ledger predicate failures for all era, except Byron.

Signed-off-by: Tripura Repalle <[email protected]>

- /governance/committee: current committee snapshot with members, quorum,
  and source NewCommittee governance action (null for the Conway-genesis
  committee).
- /governance/committee/votes: paged history of all CC member votes.
- /governance/committee/{cc_id}/votes: paged votes filtered by CIP-129 hot
  or cold credential; cold queries aggregate across hot-key rotations.

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Yurii Shynbuiev <[email protected]>

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>