FAIR-band: in-band [1/30] — operator-empirical friction during post-#11485 verification; quick-win MX-friction reduction completing the post-#11480 substrate's full operator-visibility win across INFO + WARN tiers.

Evidence: L2 (8/8 IssueSyncer specs pass including new #11486 case; 1.0s runtime) → L4 required (operator re-runs npm run ai:sync-github-workflow; WARN volume bounded to genuine vX.Y.Z → vX.Y.Z shifts, single-emit per issue).

Summary

Filter the line-377 ARCHIVE ANOMALY WARN to fire only when both oldVersion and version parse as valid semver tags via semver.valid(semver.clean(s)). Demote migration-state mismatches (one or both sides not valid semver) to a [ARCHIVE MIGRATION] DEBUG channel. Add a #warnedAnomalies instance Set (cleared at top of pullFromGitHub) to dedupe across the three #planBuckets call sites within a single sync cycle.

Empirical motivation

Operator 2026-05-16T19:33Z npm run ai:sync-github-workflow paste (SIGINT after thousands of lines):

[WARN] 🚨 [ARCHIVE ANOMALY] Issue #3285 closedAt shift detected: moving from bucket 'vneo.d.ts - Typescript definitions for all neo framework classes' to 'v8.1.0'. Dry-run review required.
[WARN] 🚨 [ARCHIVE ANOMALY] Issue #3286 closedAt shift detected: moving from bucket 'vneo.d.ts - Typescript definitions for all neo framework classes' to 'v8.1.0'. Dry-run review required.
[WARN] 🚨 [ARCHIVE ANOMALY] Issue #3287 closedAt shift detected: moving from bucket 'vNeo-Material Component Library v0.1' to 'v8.1.0'. Dry-run review required.
[WARN] 🚨 [ARCHIVE ANOMALY] Issue #7910 closedAt shift detected: moving from bucket 'v11.12.0' to 'v11.13.0'. Dry-run review required.
... (each issue line appears TWICE; thousands of lines total)

Two compounding root causes:

1. Migration-state false positives: oldVersion is derived from the cached path's directory name (IssueSyncer.mjs:310-317). During ADR 0004's clean-cut, every historically-archived closed issue has an oldVersion from the pre-cut naming scheme (title-derived strings prefixed with v), while the new time-based resolution returns a vX.Y.Z release tag. Sealed-chunk enforcement at L569/L575 already prevents these from causing any actual move — pure noise.
2. Double emission: #planBuckets is called from lines 547 (main sync), 783 (re-fetch path), and 982 (reconcile step). Each call walks the merged-issue set; same issue WARN'd at every call site.

What changed

Total: 2 files, +169 / -1 lines.

What's preserved

• Real release-boundary WARN signal remains intact at default CLI level. Genuine vX.Y.Z → vX.Y.Z shifts (e.g. #7910 v11.12.0 → v11.13.0) still emit WARN — operator visibility into actionable anomalies preserved.
• error level untouched — failures still print.
• Sealed-chunk enforcement (L569 + L575) — untouched; the WARN filter just stops emitting WARN for moves that sealed-chunk semantics already prevent.

Test plan

• 8/8 IssueSyncer specs pass (npm run test-unit -- test/playwright/unit/ai/services/github-workflow/IssueSyncer.spec.mjs, 1.0s).
• New spec asserts both axes simultaneously: migration-shape issue (oldVersion=vneo.d.ts - typescript definitions..., milestone=v8.1.0) emits 0 WARN + ≥1 DEBUG; valid-semver-shift issue (oldVersion=v11.12.0, milestone=v11.13.0) emits exactly 1 WARN containing both version strings + 0 migration DEBUG.
• Branch-from-origin/dev-tip freshness verified.
• Cross-family review APPROVED.
• @tobiu merge.
• L4 verification: operator re-runs npm run ai:sync-github-workflow post-merge; WARN volume bounded to genuine vX.Y.Z → vX.Y.Z shifts (operator's prior paste showed only 1 such case: #7910). --verbose exposes the [ARCHIVE MIGRATION] DEBUG events for diagnostic use.

Authority anchors

• Direct parent: PR #11485 (per-item INFO→DEBUG, merged 2026-05-16T19:21Z) — this is the natural FAIR follow-up completing the post-#11480 substrate's full operator-visibility win
• Substrate parent: PR #11480 (logger filtering substrate, merged) — provides the level discipline this PR builds on
• Substrate library: semver@^7.7.4 already in package.json; precedent at ai/services/github-workflow/HealthService.mjs:416
• Operator hint: 2026-05-16T19:43Z "semver" : "^7.7.4" package.json reference — challenged my original hand-rolled regex prescription; adopted in Avoided Traps section of #11486 ticket
• Empirical anchor: operator paste 2026-05-16T19:33Z showing thousands of WARN lines + SIGINT exit

Avoided traps

• Hand-rolled regex like /^v\d+\.\d+\.\d+$/: rejected per operator hint — semver library handles pre-release tags (v8.1.0-rc.1) + build metadata (v8.1.0+build.123) + future tag-format evolution correctly; regex would miss these.
• Removing the WARN entirely: rejected — real vX.Y.Z → vX.Y.Z shifts ARE actionable; only false positives during migration are quieted.
• Suppressing all [ARCHIVE ANOMALY] via a CLI flag: rejected — operator visibility into genuine anomalies must remain default-on.
• One-time migration script to rewrite cached oldVersion strings: rejected per ADR 0004's "no migration scripts. clean cut" mandate — cached metadata refreshes naturally as the sync runs; noise self-resolves after one clean-cut cycle.
• Demoting WARN to INFO: rejected — WARN level is correct for the genuine-anomaly case; demoting loses signal entirely.
• Suppressing across entire daemon lifetime: rejected — dedupe set is reset per sync cycle so issue-shifts across separate sync runs still surface; we only suppress within a single sync.

Related

• Parent context: PR #11485 (per-item INFO→DEBUG sweep, merged)
• Substrate parent: PR #11480 (logger filtering substrate, merged)
• Adjacent: GPT investigating orchestrator boot-time cadence (parallel substrate concern — Orchestrator.start() → poll() fires summary + KB sync simultaneously, root-cause of the 19:27Z wedge). Complementary lane to this WARN-tier fix.

Resolves #11486