Add private inference smoke cases

docs/roadmap/implementation.md

@@ -566,6 +566,13 @@ schema failure, and success using real validators. Derive generated success
 fixtures from the private case rather than spread private literals through tests.
 No domain criteria, configurable prompts, public fixtures, or repair loop.
 
+**Completed: 2026-10-13.** Added private text and structured inference cases,
+including an embedded schema prepared through `NewFSValidator`. Generation
+requests retain the selected target and retry allowance; local evaluation keeps
+JSON syntax and schema matching distinct. Validation passed: `go test -race
+./internal/usecase ./internal/validate`, `go vet ./...`, `go test ./...`, and
+`git diff --check`.
+
 ## Stage 14: Orchestrate HTTP Diagnostic Reports
 
 Scope: `internal/usecase.SmokeTester` and its HTTP operations.