Add descriptions for endpoints for use in openapi

src/Vegasco.Server.Api/Cars/DeleteCar.cs

@@ -9,6 +9,7 @@ public static class DeleteCar
 		return builder
 			.MapDelete("cars/{id:guid}", Endpoint)
 			.WithTags("Cars")
+			.WithDescription("Deletes a car by ID")
 			.Produces(204)
 			.Produces(404);
 	}