Cardano Updates

Replace NodeListWrapper enum in actor.rs with RunnableNode trait object,
reducing boilerplate and making the actor engine generic over any NodeImpl.
Extract new_generic<N>() to allow tests to construct simulations with
arbitrary node types.

Add TestNode — a minimal NodeImpl that ping-pongs messages between peers,
exercises timed events and CPU tasks — and run it through all 4 engine
modes (actor/sequential × single/multi-shard) plus a determinism check.

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

Introduces per-shard ClockCoordinators, Networks, and TransactionProducers
so that node groups can advance virtual time independently. Cross-shard
messages are routed through a CrossShardBroker with Connection-based
latency modeling. Each coordinator computes its own time ceiling from
peer shard times + minimum inter-shard latency (lookahead).

Currently works correctly with shard-count=1 (default). Multi-shard
execution has a deadlock that needs further investigation — likely
related to coordinator polling within nested select!/select_all.

Key changes:
- shard-count config parameter (default 1, backward compatible)
- CrossShardBroker for cross-shard message delivery
- NetworkCoordinator routes cross-shard messages to broker
- ClockCoordinator computes ceiling from peer shard lookaheads
- Fix notify race: create notified() futures before checking state
- Fix broker barrier: use TaskInitiator instead of ClockBarrier
- Per-shard TransactionProducer with filter_map for shard's nodes

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

Signed-off-by: Eric Torreborre <[email protected]>

The peer backlog queue was unbounded and could cause memory explosion.
Add leios-tx-peer-backlog-max-size config (null = unbounded) to cap it
independently. Rename the existing backlog config from
leios-tx-backlog-max-size to leios-tx-generated-backlog-max-size for
clarity. Peer txs dropped due to a full backlog are tracked separately
as PeerBacklogFull.

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

Move shard infrastructure (Shard struct, NetworkWrapper, network setup,
cross-shard routing, edge wiring, CMB peer setup, TX producers) from
sim.rs into sharding/shard.rs. sim.rs now only handles node/driver/actor
creation and top-level orchestration.

- Shard uses trait-object NetworkRunnable (BoxFuture) for type erasure
- build_shards() takes typed networks and returns Vec<Shard>
- sim.rs init_nodes() only creates nodes, drivers, actors
- Net reduction: -176 lines from sim.rs

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

Each shard (ClockCoordinator + NetworkCoordinator + TxProducer) now runs as
its own tokio::spawn'd task, enabling true parallel execution across cores.

Key changes:
- Replace select_all with tokio::spawn per shard (Simulation::run takes self)
- Cross-shard messages route directly NC-to-NC via delivery channels
- Target NC handles timing locally via its own Connection (no broker)
- CMB ceiling: min(peer.time + min_latency) with null message advancement
- Notified::enable() prevents missed notifications across concurrent tasks
- TX generation rate scaled by shard_count for consistent output
- Delete broker.rs (replaced by direct NC-to-NC routing)

4-shard runs ~2x faster than 1-shard with matching simulation results.

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

* Fixed tx pinning inaccuracy
* Added descendants to fee comparison
* Added section explaining retail isn't priced out
* Expanded MEV section
* Delta formula uses existing calculation instead of inlining it
* Added note on eviction notification

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

sim-rs: Add timestamp quantization and TX batching to sequential engine

sim-rs: Add tx backlog instrumentation and configurable cap

sim-rs: Add sequential DES engine and multi-shard parallel simulation

Pin hyperledger-identus/.github reusable workflow reference to full
SHA (f2c9e417) to satisfy SonarCloud security hotspot requiring
full commit hashes for dependencies.

Signed-off-by: Yurii Shynbuiev <[email protected]>
Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>
Signed-off-by: Yurii Shynbuiev <[email protected]>

  Update dependency bounds to match CHaP revisions (PR #1344, PR #1342):
  - ouroboros-consensus ^>=2.0 -> ^>=3.0
  - plutus-core ^>=1.59 -> ^>=1.61
  - plutus-ledger-api ^>=1.59 -> ^>=1.61