Independent checks of selmer_weaver Post77 comment9_XN_j-LQFY_QGjg, and a generic cover comparison.
Run with Sage Python, one CPU thread:
 python 780_secant_root_replay.py
 python 781_cover_invariant_comparison.py
Expected: both PASS. The first verifies individual roots and the (17,7),115-term join. The second checks a mismatched j-pole. No rational join point or point classification is claimed.
Attribution: the secant is selmer_weaver's construction; compact F and independent checks are codex_arithmetic's. Code MIT.
