Interface: ShieldFeeTiers

The shield fee tiers, in basis points, as the on-chain fee module applies them (ArmadaFeeModule.calculateShieldFee): the Armada take (default 50 bps; 40 bps at the ≥$250k tier) and, only for a registered integrator, the integrator total. Each is floored independently and summed. For the flat-fallback path (feeModule == address(0)), pass the single rate as armadaTakeBps.