docs(shadow): Lior antigravity check - preserve 3289-3293 and log drift

[AceHack]

Preserving metadata churn off-duty PRs 3289-3293 via archive-pr.ts and logging shadow lesson.

[Copilot]

Pull request overview

Archive of PRs #3289-3293 (shard-tick off-duty checkpoints) into docs/pr-discussions/ via archive-pr.ts, plus a shadow-lesson research log documenting the metadata churn pattern identified during the antigravity check.

Changes:

• Add 5 PR archive files under docs/pr-discussions/ preserving merged shard-tick PR metadata, descriptions, and review threads.
• Add a research log at docs/research/2026-05-14-shadow-lesson-log-lior-metadata-churn-off-duty.md recording the incident, diagnosis, and countermeasure.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
docs/research/2026-05-14-shadow-lesson-log-lior-metadata-churn-off-duty.md	New shadow-lesson log documenting metadata-churn incident and countermeasure.
docs/pr-discussions/PR-3293-shard-tick-2236z-off-duty-checkpoint-10-stable-ticks.md	Archived PR #3293 metadata, description, and review threads.
docs/pr-discussions/PR-3292-shard-tick-2222z-off-duty-3289-3290-merged.md	Archived PR #3292 metadata and review.
docs/pr-discussions/PR-3291-shard-tick-2221z-off-duty-3288-merged.md	Archived PR #3291 metadata and review.
docs/pr-discussions/PR-3290-shard-tick-2219z-off-duty-3287-merged.md	Archived PR #3290 metadata and review.
docs/pr-discussions/PR-3289-shard-tick-2218z-off-duty-3286-merged.md	Archived PR #3289 metadata and review.

All files are under history-surface paths (docs/pr-discussions/** and docs/research/**), where author attribution is preserved as-is and content is generated by tools/pr-preservation/archive-pr.ts. No code changes; no issues identified.

[AceHack]

Closing as substrate-mostly-redundant after per-PR triage (9 days stale, DIRTY for that window):

5 of 6 files already byte-identical on origin/main:

• docs/pr-discussions/PR-3289-shard-tick-2218z-off-duty-3286-merged.md
• docs/pr-discussions/PR-3290-shard-tick-2219z-off-duty-3287-merged.md
• docs/pr-discussions/PR-3291-shard-tick-2221z-off-duty-3288-merged.md
• docs/pr-discussions/PR-3292-shard-tick-2222z-off-duty-3289-3290-merged.md
• docs/pr-discussions/PR-3293-shard-tick-2236z-off-duty-checkpoint-10-stable-ticks.md

1 unique file preserved in branch history (HEAD fe07101) for optional cherry-pick:

• docs/research/2026-05-14-shadow-lesson-log-lior-metadata-churn-off-duty.md — multi-PR variant of the lesson logged at docs/research/2026-05-14-shadow-lesson-log-metadata-churn-3302.md (on main; covers single PR shard(tick): 2337Z — off-duty checkpoint 1-hour mark #3302). Bounded enough to cherry-pick as its own small PR if substrate is wanted.

Per .claude/rules/blocked-green-ci-investigate-threads.md stale-armed-PR resolution Pattern A (close-as-redundant) with substrate-honest preservation note.