Adds a real-infra mode for the integration test harness alongside the default
in-memory mode. Drops the previously-untested code paths (EF SqlServer
behaviors, real LDAP bind) under env-var control without breaking the
zero-infra default that CI runs.
- docker-compose.yml — minimal SQL 2022 (14331) + OpenLDAP (3894) stack
(ports chosen to coexist with docker-dev/ on 14330/3893)
- HarnessMode record reads OTOPCUA_HARNESS_USE_SQL=1 / USE_LDAP=1 from env
- SQL mode: per-harness unique DB OtOpcUa_Harness_{guid}, EnsureCreated
at startup, EnsureDeleted on dispose (best-effort)
- LDAP mode: drops StubLdapAuthService and configures real LdapAuthService
against the compose'd OpenLDAP via Authentication:Ldap:* config keys
- Microsoft.EntityFrameworkCore.SqlServer added to the test project
- README documents both modes + the macOS no-Docker caveat
Default in-memory mode unchanged — all 9 existing tests still pass.