Constant STATE_PLANE_HEAP_WORDS 

pub const STATE_PLANE_HEAP_WORDS: usize = 64;

The heap-word budget for a state-plane kernel: enough words for the largest collection any vector touches (a generous fixed LUTRAM — collections in these kernels are a handful of words; addresses index the low clog2(HEAP) bits, so an in-bounds pointer always resolves). Kept a power of two for clean address slicing.