- Merge leftovers into existing meal_box when same recipeId + cookedAt date + frozen + available.
- Store mealBoxMutations JSONB on cooking_sessions for deterministic undo.
- Undo decrements portions/remaining, discards box at zero, appends correction ledger rows.
- Mobile: undo button in cooking/[id].tsx after-flow and meal-boxes.tsx within 24h window.
- i18n undo strings across all 12 locales; parity test green.
- 6 new integration tests: merge, no cross-date merge, frozen split, undo restore, undo discard, ledger invariant.
- Update FAS3 audit doc with 3d semantics.
Closes Fas 3d
Sven (AAMOS AI)