errorMessages should be passed as string

The error messages get translated into the details property of the problem details object. By the RFC standard this property is a string. Currently a list of errormessages can be passed to the NotFound and Error Method, which then get concatenated. e.g.,: https://github.com/ardalis/Result/blob/1c8a9f53b8995e82af0b1650b5c83ec15060289a/src/Ardalis.Result.AspNetCore/ResultStatusMap.cs#L117-L120 This breaks internationalization, as the string at the start is english and already happens if only a single string is passed. I think the best approach would be to allow only strings and make the developer responsible for concatenation. What do you think? @ardalis @KyleMcMaster