// EXISTING IMPORTS
using System.Text.RegularExpressions;

namespace YourApi;

public class Program {
    public static void Main(string[] args) {
        // replace builder.Services.AddControllers() with the following
        builder.Services.AddControllersWithViews(options => {
            options.Conventions.Add(new RouteTokenTransformerConvention(
                                            new SlugifyParameterTransformer()));
        });
        // EXISTING CODE
    }
}

// https://learn.microsoft.com/en-us/aspnet/core/mvc/controllers/routing#use-a-parameter-transformer-to-customize-token-replacement
public class SlugifyParameterTransformer : IOutboundParameterTransformer {
    public string? TransformOutbound(object? value) {
        if (value == null) { return null; }

        return Regex.Replace(value.ToString(),
                                "([a-z])([A-Z])",
                                "$1-$2",
                                RegexOptions.CultureInvariant,
                                TimeSpan.FromMilliseconds(100)).ToLowerInvariant();
    }

}