Fixup user mangling

util/Seeder/MangleId.cs

@@ -0,0 +1,14 @@
+namespace Bit.Seeder;
+
+public class MangleId
+{
+    public readonly string Value;
+
+    public MangleId()
+    {
+        // Generate a short random string (6 char) to use as the mangle ID
+        Value = Random.Shared.NextInt64().ToString("x").Substring(0, 8);
+    }
+
+    public override string ToString() => Value;
+}