- spec/support/adapter_contract.rb shipped shared examples ('a simply_couch
adapter') that no spec ever included — the parity proof they document never
ran. store_contract_spec.rb now includes them against the live Store.
- concurrency_spec.rb: the suite had zero multi-threaded examples despite the
gem's core claims being CAS optimistic concurrency and Redis-replacement
primitives. Adds: counter increments under 8 concurrent writers, lock
granted to exactly one contender, with_lock mutual exclusion, stale-handle
release after TTL expiry (must not unlock the new holder), same-attribute
CAS conflict surfacing (no lost update), different-attribute auto-merge, and
a 3-thread disjoint-attribute write storm.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
