Cardano Updates

Track the maximum tx backlog length (overflow queue behind the mempool)
via events, and add a leios-tx-backlog-max-size config parameter that
applies backpressure on the tx generator when the backlog is full.
Peer transactions are unaffected by the cap.

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

Extract the hardcoded PARALLEL_THRESHOLD constant into a configurable
parallel-threshold parameter (default 10, was 32). Add engine and
parallel-threshold to config.schema.json. Disable rayon in the
determinism test since event channel ordering is non-deterministic
under parallel execution.

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

The sequential engine does not run Actor-based attackers
(EBWithholdingAttacker). Log a warning so the config isn't
silently ignored.

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

- Extract actor-model simulation (NodeListWrapper, ActorSimulation,
  init_nodes, run logic) into sim/actor.rs
- sim.rs is now a thin dispatch layer: Simulation newtype wrapping
  SimulationInner enum (Actor vs Sequential)
- Unify sequential single-shard and multi-shard builders into a
  single build_typed() function
- Group cross-shard state into CrossShardState sub-struct
- build() takes event_sender directly, creates its own infrastructure
- Remove dead code (per_shard_node_configs, init_node_impls)
- Net -407 lines across sim.rs + sequential.rs

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

- Add ShardStrategy enum (round-robin, zero-latency-clusters) configurable
  via shard-strategy in YAML parameters
- Extract sharding logic into sim-core/src/sharding/ module with pluggable
  strategy files
- zero-latency-clusters uses union-find to keep 0-latency-connected nodes
  on the same shard, improving CMB lookahead
- Log shard sizes after assignment for balance diagnostics
- Restore single-shard select! fast path (avoids tokio::spawn overhead
  that caused 50% regression vs pre-sharding baseline)
- Update config schema and test parameter files

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

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

VTBundleNotGenerated events were already emitted but silently ignored by
EventMonitor. Count them by NoVoteReason and print a breakdown after the
vote stats, making issues like LateRBHeader immediately visible.

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

The flag was parsed but never wired into the simulation.
The sim uses virtual time and already runs as fast as possible.

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

Using mixture model for sequential application of applyTx and reapplyTx

Expand Antithesis assertions and update Dockerfiles

The test-local job rebuilds all images from source and runs the full
docker-compose stack, duplicating the compilation time from the build
step. Remove it to speed up CI — Antithesis itself validates the stack
via Moog dispatch. The test-local.sh script remains for manual use.

Signed-off-by: Chris Gianelloni <[email protected]>

Signed-off-by: Chris Gianelloni <[email protected]>

Add reachable assertions to verify Antithesis test coverage reaches
important analysis states: ForgedBlock parsing, block reception,
multiple pools producing, and Leios activity.

Signed-off-by: Chris Gianelloni <[email protected]>