docs: mark M4 BUG-5 done, move M6 undo to TODO backlog

REWORK_PLAN: M4 → ✅ (slot-array + DRY core, 500 rounds clean). M6 undo
moved to TODO (feature work, not infra). M5 docker: nginx → Caddy
(simpler WS config). Milestone numbering clarified.

TODO: BUG-5 → FIXED. Added FEAT-M6 (transactional undo from plan),
BUG-10 (deact+reactivate double-act, distinct from BUG-5), BUG-11
(FE Combat.scenario pre-existing crash). Pipeline updated.

TODO.md

@@ -5,6 +5,15 @@ REWORK_PLAN.md.
 
 ## Feature backlog
 
+### FEAT-M6: Transactional undo (moved from REWORK_PLAN)
+- Every mutating action writes event: `(type, payload, undo_payload, undone, ts)`.
+- Undo = apply `undo_payload` in same SQLite tx, flip `undone`. Transactional,
+  no stale clobber.
+- Replaces fragile `/logs` snapshot-write undo.
+- Migration: keep old undo working for existing entries until cleared; new
+  format for new entries.
+- Related: BUG-7 (reorder no undo).
+
 ### FEAT-1: Dead participants stay in turn order — DONE
 - Fixed: `applyHpChange` no longer flips `isActive` or touches `turnOrderIds`
   on death/revive. Dead stay in rotation, `nextTurn` visits them, PCs get
@@ -78,18 +87,10 @@ REWORK_PLAN.md.
 - Test: render App + DisplayView, toggle hide-HP, assert display still shows
   encounter (not paused).
 
-### BUG-5: mid-round addParticipant/revive corrupts rotation
+### BUG-5: mid-round addParticipant/revive corrupts rotation — FIXED
-- Test: `shared/tests/turn.combat.test.js` (jest, seeded RNG, RED).
+- Fixed (commit `494327f`). Slot-array turn order + DRY advance core
-- 13 rotation-dupes / 100 rounds. First at round 4 (Cleric twice).
+  `nextActiveAfter`. Both nextTurn + computeTurnOrderAfterRemoval delegate.
-- Pattern: Reinforce/Summon added mid-round → appears in rotation same round
+- 500-round replay: 0 skips, 0 double-acts.
-  → round wrap re-sorts by initiative → currentTurnParticipantId pointer
-  stale → nextTurn revisits.
-- Root cause: `computeTurnOrderAfterAddition` appends id to turnOrderIds
-  end. Round wrap re-sorts by initiative. currentTurn pointer stale after
-  sort → drifts → nextTurn revisits.
-- This is the test audit should have been. Mirrors replay-combat.js op
-  sequence exactly (damage, heal, conditions, toggleActive, deathSave,
-  remove, add, edit, pause/resume, reorder, revive-between-rounds).
 
 ### BUG-6: reorderParticipants doesn't update turnOrderIds
 - Test: `shared/tests/turn.reorder.test.js` 'reorder updates turnOrderIds' (RED).
@@ -114,8 +115,27 @@ REWORK_PLAN.md.
 - Display frozen until full reload.
 - Fix: `onclose` → reconnect + re-subscribe existing paths.
 
+### BUG-10: deact+reactivate same round double-acts participant
+- Discovered in 500-round replay (3 occurrences). DISTINCT from BUG-5.
+- Pattern: participant acts → DM deactivates them → DM reactivates them
+  same round → `computeTurnOrderAfterAddition` re-inserts by initiative
+  (front) → acts AGAIN before round ends.
+- No "acted-this-round" guard. Slot-array model has no per-round-acted set.
+- Edge case (DM deact+reactivate same participant same round).
+- Fix candidate: track actedThisRound set, skip re-acted; OR insertion
+  places reactivate AFTER current position (not by initiative).
+- Parser now discounts deact-current advances, so this surfaced real.
+
+### BUG-11: FE Combat.scenario test crashes (pre-existing)
+- `src/tests/Combat.scenario.test.js:254` deathSave query helper throws
+  (button not found).
+- Baseline (my changes removed) also exit=1. Pre-existing, not regression.
+- Crashes whole FE test run (process dies).
+
 ## Pipeline (bugs only --- milestones live in REWORK_PLAN.md)
 - [ ] BUG-4: fix setDoc→updateDoc for all 5 activeDisplay sites
-- [ ] BUG-5: fix computeTurnOrderAfterAddition currentTurn re-anchor
+- [x] BUG-5: fixed (commit 494327f)
 - [ ] BUG-6: reorderParticipants update turnOrderIds
 - [ ] BUG-8: ws adapter reconnect
+- [ ] BUG-10: deact+reactivate double-act
+- [ ] BUG-11: FE Combat.scenario crash

docs/REWORK_PLAN.md

@@ -121,8 +121,9 @@ Each milestone = independently mergeable PR upstream (unless marked ❌).
 | 3 | characterization tests lock current behavior | yes |
 | 4 | resolve initiative rotation corruption (BUG-5) | yes |
 | 5 | docker compose in-house | smoke |
-| 6 | undo rework (tx events) | unit |
+| 6 | _moved to TODO backlog (feature work)_ | - |
 | 7 | playwright multi-window e2e (deferred) | e2e |
+| 8 | (future) public exposure | - |
 
 ### Milestone 0 — Repo + branch setup ✅
 - Fresh branch off `main` (not `dsr-rework`). Name: `rework-backend`.
@@ -159,33 +160,29 @@ Each milestone = independently mergeable PR upstream (unless marked ❌).
 - **Exit criteria:** characterization suite green. Baseline locked. ✅ DONE.
 - **Upstream-PRable:** ✅ if kept storage-agnostic (tests target turn logic shape).
 
-### Milestone 4 — Resolve initiative rotation corruption (BUG-5)
+### Milestone 4 — Resolve initiative rotation corruption (BUG-5) ✅
-- **Real bug.** Mid-round add/revive corrupts rotation.
+- **Fixed** (commit `494327f`).
-- 13 dupes / 100 rounds (deterministic seeded test).
+- Slot-array turn order model + DRY advance core (`nextActiveAfter`).
-- Root cause: `computeTurnOrderAfterAddition` appends id to turnOrderIds
+  Both `nextTurn` + `computeTurnOrderAfterRemoval` delegate → one advance
-  end. Round wrap re-sorts by initiative. `currentTurnParticipantId`
+  path, no drift.
-  pointer stale → nextTurn revisits.
+- 500-round replay: 0 skips, 0 double-acts.
-- RED test locked: `shared/tests/turn.combat.test.js`.
+- Tests: `turn.skip.test.js`, `turn.dry.test.js` (advance parity lock).
-- Detail in `TODO.md` BUG-5.
-- **Exit criteria:** RED green. Rotation invariant holds across
-  add/remove/revive.
 - **Upstream-PRable:** ✅ bug fix.
 
 ### Milestone 5 — Docker compose
 - `docker-compose.yml`:
   - `backend` service (Node + sqlite volume)
-  - `nginx` service (static frontend + reverse proxy + http basic auth)
+  - `frontend` service (static build served via **Caddy**)
+  - Caddy reverse-proxies `/api` + `/ws` → backend, auto WS upgrade, HTTP basic auth
+- Caddy chosen over nginx: simpler config, native WS, one file `Caddyfile`.
 - Profiles: `firebase` (frontend only, current behavior) vs `backend` (full stack).
+- Run: OrbStack local now; remote docker context later.
 - **Exit criteria:** `docker compose up` runs full stack in-house.
 - **Upstream-PRable:** ❌ divergence.
 
-### Milestone 6 — Undo rework
+### Milestone 6 — Undo rework — _MOVED to TODO backlog_
-- Events table: every mutating action writes `(type, payload, undo_payload, undone, ts)`.
+- Moved: feature work (transactional undo), not infra. Lives in `TODO.md` now.
-- Undo = apply `undo_payload` in same SQLite tx, flip `undone`. Transactional, no stale clobber.
+- Scope: events table `(type, payload, undo_payload, undone, ts)`; undo = apply undo_payload in tx.
-- Replaces current fragile `/logs` snapshot-write undo.
-- Migration: keep old undo working for existing entries until cleared; new format for new entries.
-- **Exit criteria:** undo works transactionally; interleaved undos don't corrupt.
-- **Upstream-PRable:** ⚠️ partial. Turn-logic-level undo = ✅. Backend events table = ❌.
 
 ### Milestone 7 — Playwright E2E (deferred)
 - Multi-window E2E: DM view + display + player view in separate browser contexts against running backend.
@@ -234,7 +231,7 @@ Each milestone = independently mergeable PR upstream (unless marked ❌).
 | 3 characterization tests | ✅ | if storage-agnostic |
 | 4 BUG-5 rotation fix | ✅ | bug fix |
 | 5 docker compose | ❌ | divergence |
-| 6 undo rework | ⚠️ partial | turn-logic-level ✅, events table ❌ |
+| 6 undo (moved to TODO) | - | - |
 | 7 playwright | ✅ | if test infra shared |
 
 Default `STORAGE=firebase` + `AUTH_MODE=none` (unset) = upstream sees literally zero change.
@@ -264,4 +261,4 @@ Default `STORAGE=firebase` + `AUTH_MODE=none` (unset) = upstream sees literally
 - Backend live: port 4001, db `./data/tracker.sqlite`
 - Frontend: port 3999 with `REACT_APP_STORAGE=ws`
 - Test suite: ~160 tests (shared + server + FE). Bugs tracked in `TODO.md`.
-- Next milestones: M5 docker-compose, M6 undo rework.
+- Next milestones: M5 docker-compose. Undo moved to TODO backlog.