feat: add CloudShop Aspire + TUnit example project

[thomhurst]

Summary

• Adds a comprehensive example project under examples/CloudShop/ showcasing TUnit integration testing with .NET Aspire
• Near-real-world e-commerce microservices platform with PostgreSQL, Redis, RabbitMQ, REST API, background worker, and web frontend
• TUnit test project demonstrates 15+ features including nested [ClassDataSource] injection chains, [MatrixDataSource] combinatorial testing, [CombinedDataSources], [DependsOn] workflow chains, [GenerateAssertion] custom assertions, parallelism controls, and more

Application Architecture

Project	Purpose
CloudShop.AppHost	Aspire orchestration (PostgreSQL, Redis, RabbitMQ + all services)
CloudShop.Api	REST API: Products, Orders, Auth (EF Core, JWT, Redis caching, RabbitMQ)
CloudShop.Worker	Background service consuming RabbitMQ for order fulfillment
CloudShop.Web	Minimal frontend calling the API
CloudShop.Shared	DTOs, models, events
CloudShop.Tests	TUnit test project (the main showcase)

TUnit Features Demonstrated

Feature	Where
[ClassDataSource<T>] with nested injection (3 levels)	Infrastructure fixtures (App → DB/Redis/RabbitMQ → Auth clients → Seeded data)
SharedType.PerTestSession / PerClass	All fixtures
[MethodDataSource] with Func<T>	Product, Order, Auth data sources
[MatrixDataSource] + [Matrix]	ProductSearchTests (27 combos), OrderPlacementTests (9 combos)
[CombinedDataSources]	AuthorizationTests (role × endpoint Cartesian product)
[DependsOn] chain	OrderWorkflowTests (Create → Pay → Fulfill → DB Verify)
[GenerateAssertion]	7 custom HTTP assertions (IsCreated, IsForbidden, HasJsonContent, etc.)
[NotInParallel]	Cache, Workflow, Messaging tests
[ParallelLimiter<T>]	LoadTests with custom 10/20 concurrent limits
[Repeat(N)]	LoadTests (50/20/30 iterations)
[Retry(N)]	OrderEventTests, ResilienceTests
[Timeout] + CancellationToken	Async worker verification tests
[Category]	Integration, E2E, Performance, Resilience, etc.
[Before]/[After]/[AfterEvery] hooks	Assembly setup, per-test result logging
IAsyncInitializer / IAsyncDisposable	All infrastructure fixtures
TestContext metadata	TestHooks accessing result state, display name, duration

Nested ClassDataSource Dependency Graph

DistributedAppFixture (PerTestSession) ← starts entire Aspire app
├── DatabaseFixture ← gets Postgres connection
├── RedisFixture ← gets Redis connection
├── RabbitMqFixture ← gets RabbitMQ connection
├── ApiClientFixture ← unauthenticated HTTP client
├── AdminApiClient ← authenticates as admin via JWT
├── CustomerApiClient ← authenticates as customer via JWT
└── SeededDatabaseFixture ← seeds test data via AdminApiClient

Test plan

• Solution builds with 0 errors, 0 warnings
• Verify example works with Docker running (requires PostgreSQL, Redis, RabbitMQ containers)
• Review test patterns for clarity and correctness

🤖 Generated with Claude Code