Normalize venue contract quantities before posting and derive incremental
prices and fees from cumulative order snapshots. Serialize ledger, position
and grid state updates; reconcile delayed fees and preserve rebates,
fractional quantities and native fee currencies across supported venues.
Fix product/account routing, REST adapter contracts, initial grid recovery,
and migration bootstrap registration. Add PostgreSQL concurrency and
rollback regression coverage to CI and document venue contracts/deployment.
Validation: 2716 passed, 7 environment skips, 23 integration/stress deselected;
critical lint, compile, structure, lockfile and documentation checks passed.
Real exchange order placement was not exercised. Refs #248.
TIANHE