feat: Minimal API integration — map commands and queries to HTTP endpoints (`NetEvolve.Pulse.AspNetCore`)

[samtrion]

User Story

As a developer building ASP.NET Core Minimal API applications with Pulse, I want IEndpointRouteBuilder extension methods that map mediator commands and queries directly to HTTP endpoints, so that I can eliminate the boilerplate of writing controller actions or endpoint lambdas that only forward to IMediator.

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Background

A common pattern in Minimal API projects is:

app.MapPost("/orders", async (CreateOrderCommand cmd, IMediator mediator, CancellationToken ct) =>
    Results.Ok(await mediator.SendAsync<CreateOrderCommand, OrderCreated>(cmd, ct)));

This pattern is repeated for every command and query. An IEndpointRouteBuilder integration generates these routes from CQRS message types, following conventions, and keeps the registration layer concise.

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Requirements

• Provide a new NuGet package NetEvolve.Pulse.AspNetCore targeting net8.0, net9.0, net10.0.
• Define the following extension methods on IEndpointRouteBuilder:

  // Map a command to a POST endpoint
  RouteHandlerBuilder MapCommand<TCommand, TResponse>(
      this IEndpointRouteBuilder endpoints,
      string pattern)
      where TCommand : ICommand<TResponse>;
  
  // Map a void command to a POST endpoint
  RouteHandlerBuilder MapCommand<TCommand>(
      this IEndpointRouteBuilder endpoints,
      string pattern)
      where TCommand : ICommand<Void>;
  
  // Map a query to a GET endpoint
  RouteHandlerBuilder MapQuery<TQuery, TResponse>(
      this IEndpointRouteBuilder endpoints,
      string pattern)
      where TQuery : IQuery<TResponse>;

• Each generated endpoint:
  • Binds the request body (for commands) or query string / route parameters (for queries) using the default Minimal API model binding.
  • Calls the corresponding IMediator method (SendAsync or QueryAsync).
  • Returns Results.Ok(response) on success.
  • Returns Results.NoContent() for void commands (ICommand<Void>).
  • Propagates CancellationToken from the HTTP request.
• All registered endpoints must be compatible with Microsoft.AspNetCore.OpenApi (WithOpenApi() chainable).
• The package must reference NetEvolve.Pulse.Extensibility and Microsoft.AspNetCore.Http.Abstractions.
• No dependency on NetEvolve.Pulse itself — the mediator is resolved from DI at request time.

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Acceptance Criteria

• NetEvolve.Pulse.AspNetCore package builds on all three target frameworks.
• MapCommand<TCommand, TResponse> registers a POST endpoint that dispatches via IMediator.SendAsync.
• MapCommand<TCommand> registers a POST endpoint that returns 204 No Content for void commands.
• MapQuery<TQuery, TResponse> registers a GET endpoint that dispatches via IMediator.QueryAsync.
• Endpoints correctly propagate CancellationToken.
• Generated endpoints are compatible with WithOpenApi() and produce correct OpenAPI metadata.
• Unit tests verify route registration and HTTP result types.
• Integration tests verify end-to-end HTTP dispatch through WebApplicationFactory<T>.
• XML documentation is provided for all public members.

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Out of Scope

• MVC controller integration (action filters, IActionResult return types).
• Event publishing endpoints.
• Streaming query endpoints (follow-up after feat: Streaming query support via IStreamQuery<TResponse> and IAsyncEnumerable #128).
• Authentication / authorization attributes on generated endpoints — callers chain .RequireAuthorization().
• Automatic route convention derivation from command/query type names.