🌱 Autonomous Greenhouse: 2D Control-Loop Simulator

This 2D companion drives the identical closed-loop control equations as the 3D greenhouse — proportional controllers on temperature, humidity and CO2, and a growth index built from the product of three Gaussians centered on each variable's biological optimum — but renders them as a flat side cross-section instead of an orbiting 3D scene. A roof vent swings open in proportion to temperature error, a fogger emits particle bursts whenever humidity drops below setpoint, and a CO2 injector bar glows when it is actively topping up the atmosphere, so the relationship between sensor error and actuator response is visible at a glance. Switching Auto Control off freezes every actuator and lets you watch temperature, humidity and CO2 drift back toward ambient conditions — and the growth index collapse with them — making the value of the feedback loop directly observable.