[CLAUDE] Docs: S93 closeout — PE project-code (Run #473) + Harness-16 MFE adopt + harvest

Closeout 2 task: (1) PE tree node Du an hien MA du an (8ee8f3e Run #473
prod-verified) (2) adopt Harness-16 MFE memory-fidelity-EVAL (9580098, 2-workflow PASS).

- STATUS + HANDOFF: prepend S93 (mega-line via PowerShell, S92->Prev).
- session log 2026-06-29-S93-pe-projectcode-harness16-mfe.md.
- error-ledger E-006: AS-10 2nd-fire recurrence (WF1 3-agent residual caught+reverted;
  WF2 explicit-return-only -> 0 residual) + containment guard verified S93.
- harvest (B3 single-writer APPEND): investigator-codebase (MFE ground-truth extraction-spec)
  + reviewer (MFE adoption review WF2 PASS) diaries.
- user-MEMORY index compacted 23.7->7.8KB (hook), all 38 entries kept, vocab-collision
  lesson folded into 2-workflow entry.

State unchanged (Mig 59 · 88 tables · 434 test · gotcha 76 · bundle CDn40vpV/CoPmPBg7).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/governance/error-ledger.md

@@ -47,7 +47,7 @@ Detect by **action-signature** (NOT "AI tự phán có vi phạm không"). Scan
 | agent frontmatter `model: inherit` (not `[1m]`) | gotcha #37 | procedural | — | ✅ (FD agent loaded S48) | ++ |
 | **lead = sole RAG-writer** (`store_memory` stripped, mechanized) | store_memory rebootstrap-loss (S41) + AS-3 | procedural | 2 (NamGroup + SE S41) | ✅ runtime S48 (0/8 subs) | +++ (failure-safe) |
 | session-end verify memory byte>0 | S46 0-byte (AS-8) | procedural | 1 (S46) | ✅ S49 (new mem 2355B + 0 byte-0 scan) | ++ |
-| **git-diff + chunk-count post-P2 containment** (defense-in-depth, HMW) | R1 sub-write residual (AS-10) · store_memory bypass (AS-3) | **procedural** (institutionalized S50 = standard B6 post-wave audit) | 1 (S49) | ✅ S49 (caught inv-api self-MEMORY in git-diff; chunk 2414=2414) + **S50 wave `h2-verify` (git-diff agent-memory EMPTY, chunk 2415=2415, 0 leak)** | ++ (G-015 honest — NOT allowlist-alone) |
+| **git-diff + chunk-count post-P2 containment** (defense-in-depth, HMW) | R1 sub-write residual (AS-10) · store_memory bypass (AS-3) | **procedural** (institutionalized S50 = standard B6 post-wave audit) | 1 (S49) | ✅ S49 (caught inv-api self-MEMORY in git-diff; chunk 2414=2414) + **S50 wave `h2-verify` (git-diff agent-memory EMPTY, chunk 2415=2415, 0 leak)** + **S93 (WF1 3-agent residual caught+reverted; WF2 0-residual after explicit return-only)** | ++ (G-015 honest — NOT allowlist-alone) |
 | heavy spawn → `run_in_background` | looks-frozen | **procedural** (2-strike met) | 2 (S45, S48) | ✅ S48 (FD bg) + S50 (all 4 monitor+wave spawns bg) | + |
 | RAG glob `**/`-anchored (not root) | gotcha #10 node_modules leak | procedural | 1 (S41) | ✅ (2406 clean) | ++ |
 | dump bảng env-đích TRƯỚC identifier-based data op (lock/seed-by-email) | gotcha #60 (AS-12) | episodic | 1 (S57bis lock NO-OP) | ✅ S58 (recon dump → fix `5998163` → Run #382 đo 34 locked) | ++ |
@@ -87,7 +87,8 @@ Detect by **action-signature** (NOT "AI tự phán có vi phạm không"). Scan
 - **5-why:** monitors retain `Bash` (G-015 residual write-channel; `store_memory`-strip ≠ read-only) → ≥1 wrote canonical session-end content via shell → exceeded propose-only mandate (B3 single-writer) → self-report ≠ disk (Fidelity gap) → undetected until em-main git-diff commit-gate.
 - **fix:** (process) em-main commit-gate `git diff` review = backstop, **HELD** — every changed line reviewed pre-commit → accurate / benign / correctly-placed / 0-mojibake / chunk-2415 → **adopted per AS-10 keep-if-correct** (NOT a content bug: matches what §L.b prescribes). (guard) "git-diff + chunk-count post-P2 containment" already promoted procedural this session; AS-10 now has its **first real fire**.
 - **prevention/guard:** RECOMMEND (anh / AI_INFRA, charter-v2 infra): harden monitor tool-grant — `Write/Edit` removal alone leaves Bash residual → consider a session-end hook blocking sub-Bash-write to tracked paths, OR accept commit-gate as sufficient defense-in-depth. Fidelity: if monitors write, their reports MUST disclose it → escalate 🟥 reviewer if recurs. Provenance timing-implicated, **not definitively attributable** (no false accusation).
-- **tags:** [containment-residual-write / monitor-sub / governance-docs+agent-memory]
+- **recurrence S93 (2026-06-29):** AS-10 2nd fire — 3 WF1 workflow-agents (investigator-codebase ×2 + reviewer, return-only) self-wrote agent-memory (diary append + archive self-curate + 1 stray `project_s92_*` mis-named file). git-diff post-P2 containment caught ALL → em-main reverted (kept cicd-monitor PE-deploy harvest hợp-lệ). Guard HELD again. **WF2 fix:** added explicit "RETURN-ONLY: do NOT write ANY file incl MEMORY.md" to every lane prompt → **0 residual** (instruction-fix worked, git-diff confirmed). Lesson: workflow-agent frontmatter "update MEMORY before return" fights return-only mandate → prompt MUST override + git-diff is the net (G-015, not mechanized).
+- **tags:** [containment-residual-write / monitor-sub+workflow-agent / governance-docs+agent-memory]
 
 ### E-005 — AS-1 `git add -A` on S49 governance commit (self-caught @session-end §L.a)
 - **rule (AS-1):** stage specific files, not `git add -A`/`.` (concurrency safety — `feedback_rag_mcp_recovery_concurrency`).