nx_soda_carbonation_test.nx

nx_soda_carbonation_test.nx -- smoke for nx_soda_carbonation (craft-soda C0). Proves Henry's-law carbonation + the MEASURED EXCEEDS behind "carbonation without heavy equipment": - k_H falls as water warms; anchors exact (1-3) - COLD HOLDS MORE FIZZ: 4C dissolves more CO2 than 25C at one pressure (4) - volumes unit + Henry round-trip (5-6) - NO HEAVY EQUIPMENT: 4 volumes at 4C is nanobubble-feasible (<=5 bar) (7) but the SAME target at 25C needs a saturator (>5 bar) -- the exceed (8) - NANOBUBBLE 5x faster + 5-min target (9-10) - carbonation is acid: more CO2 -> more [H+] -> lower pH, soda range (11-15) Exit code = failed assertion number; 0 = all pass.