docs(mosstank): record the VTank-source review of c406942ef; fixes deferred to Campaign VT

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

docs/plans/2026-09-06-mosstank-mode-arbitration.md

@@ -166,3 +166,52 @@ appears, and drop to peace when nothing is left and Peace Mode When Idle is on.
   MossTank/Plugin filter (79 tests, incl. `MossTankMarkupContractTests`)
   stays green with no markup changes. Owner review still owed (Opus,
   two lenses) plus the connected gate in Acceptance.
+
+### Opus review of `c406942ef` against VTank's decompiled source (2026-09-06)
+
+Verdict PASS-WITH-FIXES; owner direction is knowledge base first, so the
+fixes are DEFERRED to Campaign VT (VT2 re-judges this commit against
+`docs/research/vtank-kb/02-scheduler-and-actions.md`). Oracle citations are
+into `refs/vtank/decompiled/`.
+
+VTank facts established (cite these, do not re-derive): IdlePeace is one rule
+type `cm` registered LAST after the `"END"` sentinel (`cLogic.cs:576-577`); the
+engine runs strictly the first valid rule per tick (`cLogic.cs:220-253`); the
+buff rule `fz` (`cLogic.cs:466`) is valid whenever a buff is DUE
+(`fz.cs:69-86`), so a due buff suppresses idle-peace even between passes;
+`cm(0)` is also a pre-chain on idle loot, corpse approach, target approach and
+nav route (`cLogic.cs:530-570`, `LogicRulePreChain.cs:52-62`) — VTank drops to
+Peace BEFORE those; `fd.cs:129-133` forces Magic in the tight-waypoint case.
+Caster/mode sequencing is one idempotent per-tick function `ga.a`
+(`ga.cs:1432-1565`): preferred item → wielded item if its class maps to the
+wanted mode → profile scan in Items-page insertion order (`ga.cs:1400-1408`,
+`eq.cs:85-93`; the "no buffs" spell field is ignored); no caster → one error
+`"You must add at least one wand to your profile."` + `StopMacro()`
+(`ga.cs:1469-1472`); retry counter per tick, exhaustion runs the bugged-
+combat-state wand-use recovery, never a give-up (`ga.cs:1502-1524`); nothing
+is restored after buffing — combat re-wields through the same function.
+
+Findings to fix in VT3 (numbers from the review):
+1. BLOCKING — no-caster path re-posts the notice ~1 Hz forever (`Stop` clears
+   the latch, the auto scan restarts the pass); VTank posts once and stops the
+   macro. Fix: stop the macro (as `CombatController.Disable` does).
+2. BLOCKING — 2.0 s × `DropToPeaceModeRetryCount`(34) = 68 s > the pass's
+   30 s `StallTimeoutSeconds`, so the exhausted-budget stop is unreachable;
+   and VTank does not stop there anyway — it runs the wand-use recovery.
+3. SHOULD-FIX — arbiter drops to peace while a buff is due (1 s scan gap);
+   add "a buff is due" to the idle set.
+4. SHOULD-FIX — `MacroIdleModeArbiter.Status` is never displayed.
+5. SHOULD-FIX — profiled-caster order must be Items-page insertion order,
+   not name order (needs an ordered profile list; `CombatItemNames` is a set).
+6. SHOULD-FIX — equip stage re-issues `Equip` every frame with no cadence or
+   budget and no wieldability check (`ga.cs:1456-1460`).
+7. NIT — `Mode == Unknown` spins the preparer (arbiter treats it as hands-off).
+8. NIT — two caster predicates (`& 0x8000` vs exact); share one helper.
+9. NIT — the notice text differs from VTank's ("…to your profile.").
+10. CARRIED — the `cm(0)` pre-chains and the `fd.cs:131` Magic case are
+    unported; ours suppresses idle-peace on nav/loot instead.
+Also: `CombatController.EnterDebuffMode` (`:1373`) and the meta
+`setcombatstate` expression can fight the arbiter (no owns-action flag) —
+add `HasPendingItemDebuff` and meta activity to the idle set.
+Tests T3/T4/T5b/T5d are vacuous as written (pass with the defect present);
+T1/T2/T5a/T5c/T6 are real pins.