Add MediatR, RecActionDto, and ReadRecActionQuery

Added the `MediatR` NuGet package (v13.1.0) to enable the mediator pattern. Updated `ReC.Application.csproj` to include a project reference to `ReC.Domain`.

Introduced `RecActionDto` as a Data Transfer Object (DTO) for representing "RecAction" details, including properties for endpoints, authentication, and SQL connections.

Added `ReadRecActionQuery` to handle queries for retrieving `RecActionDto` objects, leveraging MediatR. This query filters results based on `ProfileId`.

src/ReC.Application/RecActions/Queries/ReadRecActionQuery.cs

@@ -0,0 +1,9 @@
+using MediatR;
+using ReC.Application.Dto;
+
+namespace ReC.Application.RecActions.Queries;
+
+public class ReadRecActionQuery : IRequest<IEnumerable<RecActionDto>>
+{
+    public int ProfileId { get; init; }
+}