[TarasKovalenko]

This branch finishes the .NET 10 work and takes the library from "fluent registration helpers" to something that also tells you when your container is wrong.

Container validation

ValidateRelayRegistrations() reads the descriptors and reports what is broken before a provider is ever built:

services.ValidateRelayRegistrationsOrThrow();

1 dependency injection issue(s) found:
 - [Error] CaptiveDependency: Singleton ReportScheduler (registered as ReportScheduler) captures
   scoped IUnitOfWork. The scoped instance would live for the lifetime of the application.
   Inject IRelayScopeRunner (or IServiceScopeFactory) and create a scope per unit of work instead.

It catches captive dependencies, missing registrations, singletons holding disposable transients and (opt-in) duplicates, and it understands keyed registrations, open generics, IEnumerable<T>, Lazy<T> and optional constructor parameters. Unlike ValidateOnBuild/ValidateScopes it reports everything at once and never has to resolve anything.

Lifetime helpers

• IRelayScopeRunner - run a unit of work in a fresh scope from a singleton, which is the actual fix for "cannot consume scoped service from singleton". Registered by AddRelayServices().
• AddLazyResolution() - Lazy<T> for any registered service: defers expensive construction, breaks constructor cycles, no service locator.

Decorators

Decorate<TInterface, TDecorator>(), TryDecorate and DecorateKeyed. Two behaviour changes here: decorating now wraps every non-keyed registration instead of only the last one, and the non-keyed overloads no longer match keyed descriptors - doing so used to throw, because reading ImplementationType on a keyed descriptor is invalid.

Reflection-free chains, trimming and AOT

Adapter chains used MethodInfo.Invoke per step and MakeGenericType + Activator for typed chain registration. The builders know all the types statically, so the invoker is now built at registration time and execution does no reflection at all. Hand-built steps keep the old path.

That made it possible to mark the package IsAotCompatible/IsTrimmable with real annotations. Assembly scanning and RelayTo(Func<IRelayContext, Type>) carry [RequiresUnreferencedCode] instead of a suppression, so the analyzer tells the truth.

Fixes

• assembly scanning survives a partially loadable assembly instead of throwing ReflectionTypeLoadException
• failover reports every relay failure via AggregateException; the parallel strategy no longer hides all but the first
• AddRelayServices() is idempotent
• adapters reused across chain steps are registered once
• DefaultRelayContext honours DOTNET_ENVIRONMENT
• MultiRelay takes a TimeProvider, so retry backoff is testable

Build and CI

Packages go to artifacts/packages, GeneratePackageOnBuild is off, ContinuousIntegrationBuild only applies on CI. New release.yml publishes on a v* tag or manual dispatch (needs the NUGET_API_KEY secret); CI now runs on Linux, Windows and macOS and packs on every build.

Breaking changes (2.0.0)

• IMultiRelay<T>.RelayToAll / RelayToAllWithResults take an optional CancellationToken. Call sites are unaffected; custom implementations need updating.
• Decorate<TInterface>(...) wraps every non-keyed registration and skips keyed ones.

324 tests pass, all 18 examples run, build is clean with warnings-as-errors and the trim/AOT analyzers enabled.