feat(admincli): add command for creating a user

src/FiscalOS.AdminCLI/Commands.cs

@@ -0,0 +1,9 @@
+namespace FiscalOS.AdminCLI;
+
+internal static class Commands
+{
+  public const string CreateUser = "Create User";
+  public const string Exit = "Exit";
+
+  public static readonly string[] All = [CreateUser, Exit];
+}