docs-frontmatter-cleanup: the 11 invalid last_updated frontmatter scalars quoted — double-quote convention applied uniformly (one escaped quote in phase-0.md), annotation prose verbatim; PyYAML sweep over docs/**/*.md + tasks/*.md reports 0 failures, taskgraph validate green (79 tasks); task status -> completed with Notes (recorded sweep command, date-scalar caveat) + Summary

docs/plans/implementation.md

@@ -1,10 +1,10 @@
 ---
 status: draft
-last_updated: 2026-10-10 (wave 8 decomposed — the release-readiness
+last_updated: "2026-10-10 (wave 8 decomposed — the release-readiness
 task set: seven independent entry tasks incl. the frontmatter cleanup
 and the renumber sweep, then matrix → README → publish prep → gate.
 Waves 1–7 implemented + reviewed; Findings 2–3, the fired flake-watch
-trigger, and the class-1 window's last dispositions ride wave 8.)
+trigger, and the class-1 window's last dispositions ride wave 8.)"
 ---
 
 # alkstore — Implementation plan