klever-go: SFT add-quantity `int64` overflow bypasses a finite per-nonce MaxSupply

Summary On the SFT add-quantity path the only supply bound is SFTAddCirculation, which does meta.Circulation += amount with no overflow guard, then checks if meta.Circulation meta.MaxSupply && meta.MaxSupply != 0. If amount overflows int64 and wraps negative, negative MaxSupply is false, the cap...