Documentation only, no code. Synthesizes the 3 prior audits
(Seller-Management.md, the Backoffice readiness audit, the Storefront
audit) plus BACKEND.md SS11 into one migration plan covering all 17
requested modules: Authentication, Authorization, Bootstrap, Products,
Categories, Orders, Payments, Transactions, Reviews, Analytics, Media,
Search, CMS, Builder, Settings, Notifications, Emails, Audit Logs.
Per module: current behavior, future behavior, migration strategy,
backward compatibility, risk, effort, and an endpoint classification
(No change / Minor change / Major change / New endpoint) grounded in
facts already established in the prior audits - no new exploration,
no invented specifics.
Headline finding: Orders (the Unified-vs-Split-Orders decision) is the
single highest-risk, most consequential item in the whole plan -
payments/refunds/reporting all depend on it, and it can't be resolved
by an additive field the way every other domain's seller-scoping can.
Payments stays untouched (ADR-010, frozen) under the Unified path;
only Split Orders would ever touch the payment flow, and only then
with the same scrutiny the original frozen implementation got.
Cross-cutting sections included per mission: Database changes
(one nullable seller_id column touches existing tables, everything
else is new tables - no NOT NULL migration ever required), Permission
changes, Caching (bootstrap cache key must include resolved seller
identity), Indexes, Security (seller-to-seller isolation treated with
tenant-isolation rigor), Performance, API Versioning (ties to the
already-open BACKEND.md SS2.10 decision), Migration order (14 numbered
dependency steps), and 6 recommended implementation phases (A:
Foundation through F: Operational polish).
Every phase explicitly re-asserts the non-negotiable constraint:
modules.sellerManagement.enabled=false must show zero behavioral
difference before/after each phase ships.
Linked from docs/architecture/foundation/README.md alongside the
other Seller Management docs.
