Remove the Order demo (entity/feature/repo/config/gRPC/proto) and the three
pre-marketplace migrations; regenerate a fresh InitialBaseline migration.
Stand up the REST surface (PingController + System/Ping CQRS) proving the
Mediator -> behaviors -> OperationResult -> ApiResult envelope end to end.
Close wiring gaps: register LoggingBehavior (outermost) and add the built-in
rate limiter (per-IP global + otp/auth/sensitive policies), placed before
authentication.
Add current-user + audit plumbing: ICurrentUser (HttpContext + null impls),
rename BaseEntity audit fields to CreatedAt/ModifiedAt (DateTimeOffset) +
CreatedById/ModifiedById, stamped by a new AuditFieldInterceptor.
Introduce five cross-cutting seams (IDateTimeProvider, IFieldEncryptor,
ICacheService, IObjectStorage, INotificationDispatcher) with in-memory/local
mocks registered via AddCrossCuttingSeams.
Add Baya.Test.Foundation (encryptor, audit interceptor, ping handler) and
update docs, contracts (swagger.v1.json), handoff, report, and mocks registry.
hamid