Enable correction-aware foundational D&D producers

internal/modules/dnd/shared/model_candidate.go

@@ -0,0 +1,9 @@
+package shared
+
+import "gitea.maximumdirect.net/eric/notarius/internal/framework/contracts"
+
+// ModelCandidateFromResponse returns an owned candidate for the exact validated
+// structured response produced by the shared LLM boundary.
+func ModelCandidateFromResponse(response contracts.StructuredCompletionResponse) (*contracts.ModelCandidate, error) {
+	return contracts.NewModelCandidate(response.Content, contracts.CorrectionProtocolSingleResponseV1)
+}