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+# Phase 18 deferred items
+
+Out-of-scope findings recorded during execution. They are not fixed in this phase.
+
+## 18-07 (unit tests)
+
+- **`cart.RegisterDetailsParams` has no reader (sm-paymentgateway-plugin).** The function stores a typed parameter set in `paramTypes`, and its doc says a row whose `parameters` carry `"_type": name` decodes into the registered struct. Nothing reads `paramTypes`: `decodeParameters` always returns a map. No plugin or application calls `RegisterDetailsParams` today. Making typed details parameters work means `Details` has to hold a struct beside its map, which is a design decision rather than a test-exposed bug. There are two options for a later phase: implement the typed decode, or drop the function and its README mention. `TestCartRegistry` pins what exists now: the allowlist, duplicate names, the nil constructor, and a `_type` in a row stays plain data.
+- **gofmt in sm-paymentgateway-plugin.** `mail_smoke_test.go` (from plan 04) is not gofmt-clean. 18-05 noted this too. It is left untouched.