wave-8 decomposition — the release-readiness pass: eleven tasks (seven independent entries: frontmatter cleanup — 11 docs with invalid YAML frontmatter, the renumber sweep, crate docs, the class-1 window's last dispositions, N-1, Findings 2-3, the fired-trigger flake investigation; then deployment matrix -> README -> publish prep -> review-wave-8 gate); plan wave-8 row + task set + review-rounds entry

tasks/docs-frontmatter-cleanup.md

@@ -0,0 +1,72 @@
+---
+id: docs-frontmatter-cleanup
+name: Docs frontmatter cleanup — the 11 invalid YAML frontmatters
+status: pending
+depends_on: []
+scope: single
+risk: trivial
+impact: isolated
+level: implementation
+tags: [wave-8, docs, hygiene]
+---
+
+## Description
+
+Eleven docs carry invalid YAML frontmatter: the `last_updated` values
+are unquoted multi-line plain scalars containing `: ` (colon+space)
+sequences — which YAML plain scalars cannot carry — so frontmatter
+parsers fail on them. The affected files (verified this session with a
+PyYAML parse sweep over `docs/**/*.md`):
+
+- `docs/architecture/README.md`
+- `docs/architecture/core-contract.md`
+- `docs/architecture/deployment.md`
+- `docs/architecture/engine-mem.md`
+- `docs/architecture/engine-postgres.md`
+- `docs/architecture/engine-sqlite.md`
+- `docs/architecture/overview.md`
+- `docs/architecture/queues.md`
+- `docs/plans/implementation.md`
+- `docs/research/consumer-inventory.md`
+- `docs/research/phase-0.md`
+
+The fix is quoting (the annotation prose is content — keep it verbatim;
+the family's alksocks docs use the same multi-line annotation style and
+parse fine, so the style is fine, only the quoting is missing). Choose
+the quoting that survives the values' own characters: several values
+contain apostrophes (`trim_to's`) and em-dashes; double quotes with
+`"` escaped (none observed) or single quotes with `''` escaping both
+work — pick one convention and apply it uniformly. Do not reword or
+trim the annotations.
+
+While in the sweep: confirm every other frontmatter-carrying doc under
+`docs/` parses (the POC spec/findings docs already do) and confirm the
+`tasks/*.md` frontmatters still parse and `taskgraph validate` stays
+green (they are valid today — do not touch them beyond what the parse
+check demands).
+
+## Acceptance Criteria
+
+- [ ] All 11 listed files' frontmatter parses as valid YAML (a
+      scripted parse sweep over `docs/**/*.md` reports zero failures),
+      with the `last_updated` annotation prose preserved verbatim
+- [ ] One quoting convention applied uniformly across the fixed files
+- [ ] `taskgraph validate` still green; no `tasks/*.md` content changed
+- [ ] The parse sweep command recorded in Notes so future sessions can
+      re-run it
+
+## References
+
+- docs/plans/implementation.md §Wave 8 (this cleanup rides the
+  pre-release pass)
+- docs/architecture/engine-sqlite.md (an example of the invalid
+  pattern, `status: stable` — the fix must not disturb the status
+  fields the review gates set)
+
+## Notes
+
+> To be filled by implementation agent
+
+## Summary
+
+> To be filled on completion