Atlas P10.5: the cold chain doctrine (spoilage/placement/rotation/freezer)

Cure's defensive twin, spec'd around the verified coldchain.ts sim. The
scene + cross-day carryover + inspector hygiene row are the remaining
build to make it playable; composes with the shop, the eggs' float test,
and the cure (same day-clock, opposite sign).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

KITCHEN-ATLAS.md

@@ -241,6 +241,52 @@ The pot is the pan's sibling: a heat-under-vessel with a LIQUID field.
   bucket, preserving jars ×4 (empty/full family), gravlax slab, curing
   shelf, ice cream scoop, coupe glass.
 
+### P10.5 — THE COLD CHAIN (cure's defensive twin — SIM BUILT & VERIFIED 2026-07-20)
+
+The cure is time you *want*; the cold chain is time you *fight*. `src/sim/coldchain.ts`
+is built and gate-verified — spoilage is the temperature clock pointed the other
+way: every perishable's `freshness` (1→0) only falls, on the DAY clock, and three
+disciplines sit on top. The doctrine (John's ask, 2026-07-20):
+
+> **Where you put it, how you stack it, and how long it's been there. Fresh food
+> is a clock you can slow but never stop — the fridge crawls it, the freezer
+> nearly halts it (for a texture price), the bench races it. Use the oldest first
+> or it rots in the back.**
+
+- **Spoilage clock** (`coldStep(store, days)`): `freshness -= BASE_SPOIL · perish ·
+  zoneWarmth · days`. Per-ingredient `perish` (fish/mince ~2, dairy ~1, onion ~0.3).
+  Thresholds fresh→use-soon→off→**dangerous**. Verified: raw fish over 3 days is
+  dangerous on the bench, "off" in the fridge, fresh in the freezer.
+- **PLACEMENT — zones** (`ZONE_COLD`): door 0.55 (warmest), main fridge 0.78, back
+  0.9 (coldest), freezer 1.0. Raw meat goes low, dairy mid, condiments in the door.
+  **Contamination**: a `raw` item on a higher `shelf` than a `readyToEat` item drips
+  → the lower item is flagged unsafe + docked (verified: raw-above-salad → unsafe;
+  same-shelf → safe). **Overpack**: past `ZONE_CAP` airflow chokes and the zone
+  warms (verified: crammed fridge spoils milk the sparse one kept).
+- **ROTATION — FIFO** (`pull(store, zone, fifo=true)` hands you the OLDEST): use the
+  about-to-expire stock first or it rots unused = `wasteCount` (money, P12) and, if
+  you don't notice, a `dangerous` serve. Verified: FIFO 0 waste vs newest-first 2 rot.
+- **THE FREEZER**: near-halts the clock but sets `frozen` → `usableQuality` docks
+  texture ×0.82 on thaw. Time bought, paid for later (verified: 0.93 kept vs 0.76
+  usable).
+- **The stakes**: `usableQuality` returns `{quality, safe}`. Cooking an "off" item is
+  a quality hit the judge tastes; serving a `dangerous`/contaminated one is the
+  rotten-egg beat with the safety off — a health-inspector catastrophe.
+
+**Remaining to make it playable (the scene + the cross-day layer):** a FRIDGE VIEW
+(drag stock between zones/shelves, the door/back gradient shown as a cool-tint, a
+date/age tell per item — the info tool), carry the `ColdStore` across days in the
+save (each `beginDay` calls `coldStep(store, 1)` — your fridge ages while you sleep),
+and a hygiene row on the inspector's card (`storeHealth` → fresh%/off%/contaminated/
+waste). Composes with: the shop (P12 — buy fresh = perishable, a good fridge holds
+temp = smaller `ZONE_COLD` penalty), the eggs (the float test is a freshness info
+tool), the cure (same day-clock, opposite sign). Assets (seeds 580–589 gap +): fridge
+open (zoned interior), freezer drawer, date labels 2D, a hygiene "PASS/FAIL" stamp.
+
+- **Feel that must be right:** the first time you reach for stock and it's gone off
+  on you — and the day you rotate correctly and the inspector says nothing, which
+  from him is applause.
+
 ## 7. P11 — THE BANQUET (carving, the elaborate table, the symphony)
 
 - **CARVING — the two-handed gesture John called**: the carving FORK