Use DTOs to return API requests instead of Database Schema types.

Make use of IHttpStatusCodeResults

API/Controllers/DTOs/Identifiable.cs

@@ -0,0 +1,18 @@
+using System.ComponentModel;
+using System.ComponentModel.DataAnnotations;
+
+namespace API.Controllers.DTOs;
+
+/// <summary>
+/// <see cref="API.Schema.Identifiable"/>
+/// </summary>
+public record Identifiable(string Key)
+{
+    /// <summary>
+    /// Unique Identifier of the DTO
+    /// </summary>
+    [Required]
+    [Description("Unique Identifier of the DTO")]
+    [StringLength(TokenGen.MaximumLength, MinimumLength = TokenGen.MinimumLength)]
+    public string Key { get; init; } = Key;
+}