adding completions

Server/Models/CompletionDTO.cs

@@ -0,0 +1,9 @@
+namespace Server.Models;
+
+public class CompletionDTO {
+    public DateTimeOffset Date  { get; set; }
+    public Guid Id              { get; set; }
+    public Guid UserId          { get; set; }
+    public string Map           { get; set; }
+    public double Time          { get; set; }
+}