Detection Coverage Drift 2D: ATT&CK Validation Cadence Simulator

Detection rules don't fail loudly — they rot quietly. This 2D simulator renders a live MITRE ATT&CK coverage matrix as a flat heatmap where every technique's detection confidence decays over simulated time as the environment drifts, and only comes back up through automated re-tests on a cadence you control or an on-demand purple-team validation pass. Simulated attacker probes land on random techniques and are silently missed whenever local coverage has decayed too far, and a rolling history chart tracks average coverage and the cumulative missed-detection rate over time, so you can watch exactly how validation cadence trades off against missed-detection rate.