[regression] Daily CI Regression Audit — 33829765688 #58358

Top failure patterns (from last 20 ci.yml runs, run IDs 33765149822–33829250880):

1. Lock file drift ("Check workflow markdown/lock drift" job) — dominant, repeated pattern.
   Seen in runs 33829250880 and 33828991254 (both most recent). The compiled .lock.yml files no longer match their .md sources for the same 6 workflows every time:
   archie.lock.yml, contribution-check.lock.yml, daily-file-diet.lock.yml, glossary-maintainer.lock.yml, smoke-issues.lock.yml, technical-doc-writer.lock.yml.
   This indicates recent commits touching these .md sources were pushed without running make recompile, or the compiler output has non-deterministic/drifting output for these specific workflows (worth checking if the same 6 files recur across many days — suggests a systemic compiler/formatting issue rather than one-off human error).

2. ci-doctor.md compile failure due to bad frontmatter — likely a stray git-merge-conflict marker.
   Run 33822808920, job "update", step "Test update command (dry-run)":
   error: invalid header option: "|||||| base (original)" at .github/workflows/ci-doctor.md:5:1.
   The string |||||| base (original) is a git merge-conflict marker — this suggests ci-doctor.md was committed with an unresolved merge conflict, breaking frontmatter parsing for the update workflow's dry-run compile check.

3. High cancellation rate (6/20, 30%) likely from concurrency-group supersession on rapid successive pushes to main, rather than genuine failures — not flagged as a regression but adds noise to the failure-rate signal.

No open issues labeled bug/regression currently track either of these patterns.