nx_artifact_root_gate.nx

nx_artifact_root_gate.nx -- proves the shared resolver finds an artifact that IS there under a different root, and does NOT invent one that is not. Both halves matter: the defect it exists to kill was a false NEGATIVE (real files reported missing), and the obvious over-correction is a false POSITIVE (a resolver so eager it "finds" something for any input, which would ground claims against the wrong file). The gate builds its own fixture tree and its own roots conf, so it never depends on -- or perturbs -- production config. license_tier: ORIGINAL expect_exit: 0