The existing CRITICAL pattern in injection-patterns.mjs only fires when
a comment body contains AGENT/AI/HIDDEN markers. Adversaries can drop
the marker and still hide instructions inside <!-- ... --> for any
agent that reads page source. This generalizes the comment scan: every
comment body is HTML-entity-decoded and run through the full
injection rule set. The existing keyword-restricted pattern still
fires (defense-in-depth).
Emits at the strongest tier with category html-comment-injection.
+3 tests (65 → 68).
Refs: Batch B Wave 4 / Step 11 / v7.2.0