The Clans bad handling of duplicate IBBS packets

If the same Attack packet is delivered multiple times, The Clans will parse it multiple times, which generates multiple Attack Result packets, which can not only perform the attack multiple times, but also has multiple armies return. This trivially leads to large numbers of followers and high rewards.

IBBS processing should use a small sliding window on "next" packet allowance, and absolutely not allow the same packet to be processed multiple times in a row.