Catalyst Volcano Plot (2D): Kinetic Monte Carlo Sabatier Explorer

This 2D companion to the catalyst volcano-plot simulator replaces the scripted 3D animation with an actual working kinetic Monte Carlo engine: hundreds of independent lattice sites, each an honest two-state Markov chain, hop between empty and bound at Arrhenius rates derived from the same Brønsted–Evans–Polanyi scaling relation and binding-energy descriptor ΔE. Every real turnover (a bound site releasing back to empty) is tallied, and the resulting measured flux is plotted live alongside the closed-form harmonic-mean formula for turnover frequency — watch the two converge as more site-seconds of simulated time accumulate, and see how the same asymmetry between adsorption and desorption barriers that produces the volcano shape also produces the "starved" and "poisoned" regimes as genuinely-simulated near-zero turnover rates, not just an animation slowdown.