nx_phys3d_gate.nx

nx_phys3d_gate.nx -- gate for the unified sovereign rigid-body core (the 07-01 census's named gap). The CLASSIC engine proofs, all integer-deterministic: T1 integrator exactness (free fall matches the loop-computed analytic sum EXACTLY) T2 restitution: e=0.5 bounce apex ~1/4 of drop height; e=0 body RESTS on the ground and stays T3 THE STACK: 8 dynamic boxes on a static ground -- 1200 ticks, bounded drift, ALL ASLEEP at the end T4 friction is real: mu=0.78 slider STOPS; mu=0 slider KEEPS SLIDING (same push, same ticks) T5 determinism: two worlds, same script -> all body slots IDENTICAL after 500 ticks T6 elastic head-on equal masses: velocities SWAP integer-exact (e=1) T7 inelastic head-on (e=0): both stop (momentum symmetric) license_tier: ORIGINAL expect_exit: 0