vmall/openspec/changes/add-favorites/tasks.md

1. Persistence and backend contract

• 1.1 Add migration 0015_favorites.sql with explicit product/shop foreign keys, exactly-one-target check, cascading deletes, customer indexes, and partial unique indexes for each target kind.
• 1.2 Add shared discriminated favorite summary/query types and listFavorites, addProductFavorite, removeProductFavorite, addShopFavorite, and removeShopFavorite methods to @vmall/shared.
• 1.3 Implement apps/api/src/modules/favorite/ repository, service, DTO, handlers, and module registration with customer-only target-resource routes.
• 1.4 Implement visible-target validation, idempotent upserts/deletes, ownership filtering, pagination totals, optional target filtering, and SQL-hydrated product/shop summaries.

2. Backend behavioral proof

• 2.1 Add isolated API integration coverage for exactly-one-target and uniqueness constraints, customer ownership, missing/unavailable targets, repeated add/remove, product/shop listing, target filtering, pagination, and unavailable-target hiding.
• 2.2 Run the focused favorites integration tests and then run cargo test -p vmall-api twice to prove list tests remain green against the non-truncated shared test database.

3. Adapter and live-domain wiring

• 3.1 Implement the five favorite client methods in apps/mall/mock/api.ts with per-session mutable fixture state and the same idempotent/filter/pagination behavior.
• 3.2 Add the favorites domain and exact shared-client method picks to Mall API selection and enable it in the default/live runtime configuration.
• 3.3 Add or adjust bilingual favorite loading, mutation, and failure strings through the existing Mall locale source without introducing per-page hard-coded copy.

4. Mall favorite surfaces

• 4.1 Replace product-detail local heart state with authenticated filtered lookup and idempotent live add/remove, preserving the detail URL through sign-in and disabling concurrent clicks.
• 4.2 Replace store-detail local favorite state with the same persisted authenticated behavior for shop targets.
• 4.3 Replace apps/mall/pages/user/favorites.vue fixture joins and local deletion with paginated product/shop API results and persisted removal.
• 4.4 Replace buyer-dashboard MOCK_FAVORITES preview and count derivation with a bounded live product-favorites query and remove all page-level favorites fixture imports.

5. Verification and tracker cleanup

• 5.1 Seed or create a deterministic customer product and shop favorite, run the API plus Mall, and browser-smoke add, reload persistence, buyer-center listing/removal, store favorite, and anonymous sign-in redirect.
• 5.2 Build all three frontends because the shared API contract changes: pnpm --filter @vmall/mall build, pnpm --filter @vmall/shop-admin build, and pnpm --filter @vmall/admin build.
• 5.3 Mark Favorites implemented in docs/TBD-marketing.md, update the README mock boundary, check every OpenSpec task, and run openspec change validate add-favorites --strict plus openspec validate --all --strict.