Subscriptions drift on both stores (Apple prices in the dry run, localizations, group names, attributes, territories, intro offers reported; Play offer phases and prices, other-regions price, dropped regions gated, grace period, --prune-languages); pitfall 104, CHANGELOG; test fixtures for the new reads

skills/store-pitfalls/SKILL.md

@@ -1251,3 +1251,17 @@ that fails without the fix (see CONTRIBUTING.md).
 - **Do:** update storebound; the warning was false.
 - **Guard:** `readProjectEntitlements` in `cli/apple/signing.ts` compares forward-slash paths on every OS
   (`tests/entitlements-ref.test.ts`).
+
+## 104. An existing store item differs from the config and the run said nothing
+- **Symptom:** `apple iap --yes` updated only missing localizations of live consumables while the config's USD prices
+  (12.99 / 129.99 / 649.99) differed from the store (9.99 / 99.99 / 500.00); the dry run showed no price, and changed
+  names and descriptions were never sent. An audit found the same class in 24 places (subscriptions, offers, app
+  price and availability, events, custom pages, review details).
+- **Cause:** existing items were checked for existence only, not compared field by field.
+- **Do:** read the dry run: every difference of an existing item is a row (old -> new). Text changes are sent;
+  prices, dropped regions and removed territories need `--allow-price-changes` / `--allow-availability-changes`
+  (the owner's call); fields Apple cannot edit (family sharing on, offer-code and win-back campaigns, intro offers,
+  subscription period) are named, never changed.
+- **Guard:** `iapLocalizationChanges` / `iapAttributeChanges` / `availabilityChange` (`cli/apple/iap.ts`), the
+  subscription helpers in `cli/lib/subscriptions.ts`, `planAppInfo` / `reviewDetailDiff`, `campaignDiff`,
+  `winBackDiff`, `eventAttrDiff`; tests `apple-iap-drift`, `subscriptions-drift`, `appinfo-drift`, `misc-drift`.