Shared test definitions for rustvello backend implementations.
This crate provides reusable async test functions that exercise the
abstract traits ([Broker], [Orchestrator], [StateBackend], etc.)
Each backend crate (mem, sqlite, redis, …) calls these functions with
its own concrete implementation to verify consistent behavior.
Usage
// In crates/rustvello-mem/tests/suite.rs
use MemBroker;
async