[CLAUDE] Docs: chốt session 9+ housekeeping log + STATUS+HANDOFF+migration-todos update

Session log mới `2026-05-04-1900-chot-session-9-plus-housekeeping.md`:
chốt 4 commit Session 9+ post-Session-9 (Audit 2026-05 + Inbox PE +
Housekeeping docs + User Manual 7 file rewrite). Full narrative
+ context + lessons + stats + cảnh báo session 10+.

STATUS Recently Done +1 row mới (User Manual rewrite 16c2c9c) +
Phase header refresh "Session 9+ chốt" + "7 file User Manual ~86 KB
compact end-user style".

HANDOFF Housekeeping section +1 mục User Manual rewrite + thêm note
"User Manual style rule mới chốt session này": phân biệt với §6.5
(end-user docs vs dev docs).

migration-todos thêm section "Session 9+ housekeeping done" với 3
task tick (audit + Inbox PE + User Manual).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docs/changelog/migration-todos.md

@@ -213,6 +213,12 @@ Session log: `2026-05-04-1230-chot-session-8-2-stage-dept-approval.md`.
 - [x] **Rule mới rules.md §6.4** — Audit + compact MD định kỳ (cadence + checklist + anti-pattern)
 - [x] **rules.md §9.4** — Mở rộng skill audit cross-ref §6.4
 
+### ✅ Session 9+ housekeeping done (2026-05-04 — sau Session 9 close)
+
+- [x] **Audit định kỳ 2026-05** — combined skill + doc drift (commit `7dc0233`). Log `skill-audit-2026-05.md`.
+- [x] **Optional polish — fe-user Inbox PE section** (commit `332a90f`). HĐ + PE 2 section trong InboxPage.
+- [x] **User Manual 7 file rewrite compact** (commit `16c2c9c`). End-user style: bỏ field/error tables, giữ numbered steps đơn giản. ~86 KB total.
+
 ### A. Hard blockers (chờ user / ops)
 
 - [ ] UAT thật 1 tuần với 2-3 user (30 demo: 16 sample + 14 Solutions thật)