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MareSynchronosAPI/Data/UserData.cs

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+using MessagePack;
+
+namespace MareSynchronos.API.Data;
+
+[MessagePackObject(keyAsPropertyName: true)]
+public record UserData(string UID, string? Alias = null)
+{
+    [IgnoreMember]
+    public string AliasOrUID => string.IsNullOrWhiteSpace(Alias) ? UID : Alias;
+}