Add car name duplicate validation

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

@@ -1,5 +1,6 @@
 using FluentValidation;
 using FluentValidation.Results;
+using Microsoft.EntityFrameworkCore;
 using Vegasco.Server.Api.Authentication;
 using Vegasco.Server.Api.Common;
 using Vegasco.Server.Api.Persistence;
@@ -19,7 +20,8 @@ public static class CreateCar
 			.WithTags("Cars")
 			.WithDescription("Creates a new car")
 			.Produces<Response>(201)
-			.ProducesValidationProblem();
+			.ProducesValidationProblem()
+			.Produces(409);
 	}
 
 	public class Validator : AbstractValidator<Request>
@@ -59,10 +61,18 @@ public static class CreateCar
 
 		Car car = new()
 		{
-			Name = request.Name,
+			Name = request.Name.Trim(),
 			UserId = userId
 		};
 
+		var isDuplicate = await dbContext.Cars
+			.AnyAsync(x => x.Name.ToUpper() == request.Name.ToUpper(), cancellationToken);
+
+		if (isDuplicate)
+		{
+			return TypedResults.Conflict();
+		}
+
 		await dbContext.Cars.AddAsync(car, cancellationToken);
 		await dbContext.SaveChangesAsync(cancellationToken);