Builds a container from the same AddOtOpcUa* methods Program.cs's driver branch
calls (AddOtOpcUaLocalDb / AddGrpc / AddOtOpcUaHealth / AddOtOpcUaObservability) and
resolves through it - DI extensions have shipped inert three times in this family.
Does not boot the real host: WebApplicationFactory<Program> would start hosted
services (Akka, OPC UA server, ValidateOnStart) needing SQL + a mesh, per D-5. The
seam under test is DI resolution, so the container is built and resolved without
starting.
Five pins: ILocalDb singleton + exact replicated-table set; IDeploymentArtifactCache
-> concrete; default-OFF ISyncStatus; localdb-replication health check registered and
constructible; admin-only graph has NO ILocalDb and does not demand LocalDb:Path.