nx_costest_gate.nx

nx_costest_gate.nx -- GATE for the cost estimator (nx_costest_lib), driven IN-PROCESS: known-answer teeth on the integer sqrt, the deci-u parser and printers, the three-point aggregate (root-sum-square band beside the correlated sum), the quantile rank rule and the derived distinct-rank floor, the compute-cost rules, and the calibration census over planted plan rows (a rung calibrated from two journal rows, a rung whose last land row wins, a rung with no declared cost EXCLUDED BY NAME, a rung whose only row is its land row EXCLUDED BY NAME, a journal row naming no rung COUNTED, a non-integer epoch IGNORED), then the ledger line written and read back through the one grammar, a malformed ledger REFUSED and an absent one reported absent. Every fixture asserts its own condition first; the neg-controls are named. license_tier: ORIGINAL No hw writes (Rule 26).