Spring Cleaning 2026 Day 3: h3 & fixing ascii boxes

H3 and Fixing ASCII Boxes Smaller updates today. H3 https://github.com/mattsta/h3 H3 has been either mostly complete, closed, or abandoned for a while, but there’s still room for improvement. I’m forking it here with my own refactors and improvements: https://github.com/mattsta/h3 Performance — the headline numbers Single-cell hot path API upstream → optimized speedup cellToBoundary 0.50 µs → 0.23…