docs(openspec): plan shop coupons, accounts, points, flash sales, and group buying

Capture exclusive promotion composition, empty-group cancel, and mall surface scope so the five marketing changes can be implemented without stacking or lifecycle ambiguity.

Co-authored-by: Cursor <cursoragent@cursor.com>

docs/TBD-marketing.md

@@ -15,41 +15,65 @@ mock data and the page's `~/mock/data` import in the same change.
 
 ---
 
+## Planning report — 2026-09-18
+
+Five independent, implementation-ready OpenSpec changes were created and validated strictly:
+
+| Change | Business boundary | Prerequisite |
+| --- | --- | --- |
+| `add-shop-coupons` | Shop templates, customer claims, per-shop checkout redemption, and cancellation restoration | None |
+| `add-customer-accounts` | Monetary/points accounts, append-only ledger, and live account stats | None |
+| `add-points-mall` | Platform points catalog, atomic redemption, customer history, and admin fulfillment | `add-customer-accounts` must archive first |
+| `add-flash-sales` | Timed sessions, SKU activity inventory, limits, and checkout pricing | None |
+| `add-group-buying` | Activities, group lifecycle, paid membership, and payment-time capacity | None |
+
+Each change has `proposal.md`, `design.md`, `specs/`, and `tasks.md` in
+`openspec/changes/<change>/`; all five passed `openspec change validate <change> --strict`.
+Their planning documents use generic B2B2C storefront terminology rather than a source-project
+name.
+
+**Captured decisions:** coupons are template plus customer-owned snapshot and one per shop order;
+activity-priced shop orders (flash or group) reject coupons; a SKU cannot be in overlapping flash
+and group windows; account debits use guarded atomic updates with immutable entries; points
+redemption uses a separate order lifecycle and demo points are seed-credited through the ledger;
+flash sales use activity-reserved stock and server-calculated prices; group seats are claimed at
+payment rather than checkout; an unpaid opener cancel closes an empty group; catalog product-detail
+does not show flash or group prices in these changes.
+
+**Recommended implementation order:** start `add-customer-accounts` and/or
+`add-shop-coupons`; archive accounts; then `add-points-mall`; implement `add-flash-sales` after
+the coupon checkout shape is settled; implement `add-group-buying` last because it expands the
+payment state machine. **Favorites** can be a separate OpenSpec change at any time (no order
+coupling). The deferred designs below intentionally have no change yet.
+
 ## Mock holdouts with a mall UI today
 
-- [ ] **Coupons** — `user/coupons.vue` lists `MOCK_COUPONS`; `goods/[id].vue` shows a
-  claim strip off the same fixture.
-  Missing: `coupon_templates` (shop-issued: amount/threshold/window/stock), `coupons`
-  (user-held, order-bound status). APIs: `GET /api/coupons` (mine),
-  `POST /api/coupons/claim` (from a template), shop-admin template CRUD, and checkout
-  application (select → discount minor → bind to order). Money math stays minor units.
+- [ ] **Coupons** — covered by in-progress `add-shop-coupons` (not yet applied). Mall still
+  reads `MOCK_COUPONS` until that change is implemented.
 - [ ] **Favorites** — `user/favorites.vue` lists `MOCK_FAVORITES` (products tab +
-  stores tab); `user/index.vue` derives counts from it.
-  Missing: `favorites(user_id, product_id | shop_id)` with a partial unique index per
-  target kind. APIs: `GET/POST/DELETE /api/favorites` (product & shop variants).
-- [ ] **Account stats** — `user/index.vue` shows `USER_STATS` (balance 128.00, points
-  2680, frozen 0) and `integral.vue` reuses the points figure.
-  Missing: balance/points accounts and ledgers (`money_logs` in the reference).
-  MVP shape: `GET /api/me/stats` returning `{ balance_minor, points, frozen_minor }`;
-  real ledgers only when a flow (recharge, refund-to-balance, points earn/spend) needs them.
+  stores tab); `user/index.vue` derives counts from it; `goods/[id].vue` heart is local
+  `ref(false)`. Ready for its own OpenSpec change whenever convenient: no checkout
+  coupling. Schema: `favorites(user_id, product_id | shop_id)` with a partial unique
+  index per target kind (see deferred design). APIs: `GET/POST/DELETE /api/favorites`.
+- [ ] **Account stats** — covered by in-progress `add-customer-accounts` (not yet applied).
+  Mall still reads `USER_STATS` until that change lands. The change already includes
+  append-only ledgers and guarded mutation; public entry listing stays out of scope.
+  Frozen balance is a reserved kind and stays zero until a freeze flow exists.
 
 ## Marketing pages that are display-only mock
 
 These exist as full pages (`seckill.vue`, `collective.vue`, `integral.vue`) linked from
 the home navigation; all three read fixtures directly.
 
-- [ ] **Seckill （秒杀）** — `SECKILL_SESSIONS` + `seckillProducts()` (price override,
-  sold %).
-  Missing: `seckill_sessions`, `seckill_products` (activity price, isolated stock),
-  `GET /api/seckill/sessions`, and checkout price resolution honouring the active session.
-- [ ] **Collective / 拼团** — `collectiveProducts()` (need/joined counts).
-  Missing: `collective_activities`, `collective_groups` (open/join/expire, success on
-  fill); orders bind to a group; refund/rollback policy on expiry.
-- [ ] **Integral mall / 积分商城** — `INTEGRAL_PRODUCTS` + points from `USER_STATS`.
-  Missing: points ledger (earn/spend), `integral_products`, points-denominated checkout
-  (`integral/orders` in the reference).
+- [ ] **Seckill （秒杀）** — covered by in-progress `add-flash-sales`. Page still reads
+  `SECKILL_SESSIONS`. Catalog product-detail does not show flash prices in that change.
+- [ ] **Collective / 拼团** — covered by in-progress `add-group-buying`. Page still reads
+  fixture counts. Paid seats at payment; unpaid opener cancel closes an empty group.
+- [ ] **Integral mall / 积分商城** — covered by in-progress `add-points-mall` after
+  `add-customer-accounts` archives. Demo spendable points are seed-credited through the
+  ledger; earning campaigns stay out of that change.
 
-## Domains the reference has and this MVP does not (no UI here)
+## Domains typical B2B2C storefronts have and this MVP does not (no UI here)
 
 Recorded so the gap is explicit, not because all of them belong in scope:
 
@@ -58,15 +82,41 @@ Recorded so the gap is explicit, not because all of them belong in scope:
   Missing: `order_comments` (order-item bound, rated, replyable), public read on product
   pages, shop reply, admin moderation. Writing/moderating/displaying reviews is a feature
   with its own lifecycle.
-- [ ] **Distribution / 分销**, **cashes / 提现**, **money logs** — qwshop user-center
-  modules; no mock, no UI, no model here.
-- [ ] **Help center / articles** — nav links exist in the footer (`帮助中心`); no article
-  model. Cheap version: static content pages; full version: admin-managed articles.
-- [ ] **OAuth login, SMS/captcha** — reference `users/oauth` + captcha plugin; here auth
-  is email+password only.
+- [ ] **Distribution / 分销**, **cashes / 提现** — common B2B2C account modules; no mock,
+  no UI, no model here. Customer-account freeze/credit is the intended foundation.
+  Public money-log listing is not in `add-customer-accounts`. Deferred design notes below.
+- [ ] **Help center / articles** — header nav `shell.nav.help` currently links to `/user`;
+  the footer has no help links. No article model. Cheap version: static locale pages;
+  full version: admin-managed articles.
+- [ ] **OAuth login, SMS/captcha** — common storefront plugins; here auth is email+password only.
 - [ ] **Freight templates / 运费模板** — shop-side shipping-fee rules; checkout currently
   charges no shipping at all.
 
+## Deferred designs from general B2B2C storefronts
+
+These patterns are recorded for later product discovery only. They are not approved scope,
+have no OpenSpec change, and must be redesigned under VMall's minor-unit, JSONB, RBAC, and
+transaction rules before implementation.
+
+- [ ] **Threshold reductions / 满减** — merchant rules need a shop scope, localized name,
+  threshold and reduction in one currency, active window, and an explicit best-eligible rule.
+  Coupon vs flash/group is already exclusive (reject coupon on activity-priced shop orders).
+  Keep 满减 independent from coupons until a stacking policy with those shop coupons is specified.
+- [ ] **Favorites** — do not use a polymorphic `target_id`/type pair. Keep the existing
+  product-or-shop design with separate nullable foreign keys, a target-kind check, and one
+  partial unique index per target type so duplicate claims are impossible. This can be a
+  dedicated OpenSpec change; it is the smallest remaining mall mock with a UI.
+- [ ] **Reviews / 评价** — a future review belongs to a fulfilled order item, not just a
+  product. Preserve an immutable rating/content snapshot, allow one shop reply, and make
+  public visibility and platform moderation explicit lifecycle states.
+- [ ] **Distribution / 分销** — a future merchant activity may configure per-product levels,
+  but commissions must be created as order-item ledger entries and become payable only after
+  the order reaches its chosen settlement condition. Do not use floating commission rates or
+  mutate a balance without a ledger entry.
+- [ ] **Withdrawals / 提现** — model a payout request with account, amount minor, fee minor,
+  destination snapshot, and `requested → approved | rejected | paid` transitions. Funds must
+  be frozen and released or debited atomically with the transition.
+
 ## Deliberately out of scope — does not block deleting this file
 
 - **The fixed-data adapter itself** (`apps/mall/mock/api.ts`, `~/mock/data`): the