Happy flow for creating realms works

But needs more validating...

IdentityShroud.Core/DTO/JsonWebToken.cs

@@ -0,0 +1,39 @@
+using System.Text.Json.Serialization;
+
+namespace IdentityShroud.Core.Messages;
+
+public class JsonWebTokenHeader
+{
+    [JsonPropertyName("alg")]
+    public string Algorithm { get; set; } = "HS256";
+    [JsonPropertyName("typ")]
+    public string Type { get; set; } = "JWT";
+    [JsonPropertyName("kid")]
+    public string KeyId { get; set; }
+
+}
+
+public class JsonWebTokenPayload
+{
+    [JsonPropertyName("iss")]
+    public string Issuer { get; set; }
+    [JsonPropertyName("aud")]
+    public string[] Audience { get; set; }
+    [JsonPropertyName("sub")]
+    public string Subject { get; set; }
+    [JsonPropertyName("exp")]
+    public long Expires { get; set; }
+    [JsonPropertyName("iat")]
+    public long IssuedAt { get; set; }
+    [JsonPropertyName("nbf")]
+    public long NotBefore { get; set; }
+    [JsonPropertyName("jti")]
+    public Guid JwtId { get; set; } 
+}
+
+public class JsonWebToken
+{
+    public JsonWebTokenHeader Header { get; set; } = new();
+    public JsonWebTokenPayload Payload { get; set; } = new();
+    public byte[] Signature { get; set; } = [];
+}