Hub grow-mat root-zone vote reads past its arrays: probes[2]/vote[2] looped to i < 4 (undefined behaviour, phantom probe can drive the mat)

Found 2026-09-14 04:2x from a GCC warning during the tent-pressure hub OTA: ‘iteration 2 invokes undefined behavior [-Waggressive-loop-optimizations]’. When pot3/pot4 were stripped (9f2663a/bad1b3b, 2026-09-10) the arrays shrank to float probes[2] / bool vote[2] but the loop stayed for (int i = 0; i < 4; i++). i = 2, 3 read stack memory: a non-zero garbage vote plus a garbage float inside the 5-45 C plausibility window becomes a phantom probe in rz_min / rz_max, so the mat can turn on, off, or trip the RUNAWAY flush on garbage. Live on the hub since 2026-09-10. Fix: bound i < 2 (overnight sweep branch), esphome config check, reflash in the dark window.