chore(agents): CI failures reach fix runs; audit runs the comment review; fewer pushes; Stryker failures say why

[V3RON]

From the #437 delivery (PR #449). Each change targets a class of problem, not that run's particular defects.

• CI failures reach fix runs. Every push cancels the CI run before it, so the head's checks were always pending at the pre-round check. A real e2e failure stayed red through 4 review rounds unseen. The new .agents/scripts/ci-failures.mjs <pr> prints the failed tests of the newest finished run of each workflow on the branch. deliver runs it before every review round and fix run, and puts its failures into the fix run's fixes. Implementers use it for their ci: value.
• Audit runs the comment review. The comment-reviewer brief now lives in its own definition, so the reviewer and the implementer's audit spawn it the same way. Audit deletes what it flags instead of rewording. The claims review now judges only whether a comment is true. Whether a comment should exist is the comment review's call.
• Rewritten docs and comments cite the code. In fix mode, each fact in new text names the path:line that shows it. Fixes that brought in new false claims cost rounds in Core knows physical devices: the device union, its state machine, and every virtual-only path leaves them alone #436 and simlock device add / remove: an admin enrolls and unenrolls physical devices #437.
• Fewer pushes. Each push runs mutation testing for minutes. Implementers now push when they need the mutant list, and once before the report. They read the whole push output.
• Stryker failures say why. mutate.mjs prints the last lines of Stryker's error output at the end and exits 2. Before, it exited 1, and the hook then printed "Mutants survived". A crash on feat(enrollment): simlock device add / remove enroll and unenroll physical devices #449 couldn't be reproduced at the same commit, and its cause was lost to | tail.

Tests: src/ci-failures.test.ts (new) and src/mutate.test.ts (one new case). Every check was probed by breaking the script.