Instrumentation Amplifier (In-Amp) V_CM vs V_OUT Diamond-Plot Clipping & Bias-Return Guard

Deterministic 3-op-amp internal node boundary system V_A1 = V_cm + G_1*V_diff/2, V_A2 = V_cm - G_1*V_diff/2 convex-polygon (Diamond Plot) intersection with stage-1/stage-2 input/output rails engine (.json, .csv, .sp) built for Texas Instruments (INA), Analog Devices (AD8221/AD8422), Linear Technology, LTspice — zero-upload ephemeral Wasm RAM execution.