feat(cpp-object-oriented-modular-refactoring): step 5 - solver-workflow-google-style

include/fesa/results/results_writer.h

@@ -0,0 +1,28 @@
+#ifndef FESA_RESULTS_RESULTS_WRITER_H_
+#define FESA_RESULTS_RESULTS_WRITER_H_
+
+#include <filesystem>
+#include <vector>
+
+#include "fesa/analysis/analysis_state.h"
+#include "fesa/core/diagnostic.h"
+#include "fesa/core/status.h"
+#include "fesa/model/domain.h"
+
+namespace fesa {
+
+/// @brief Isolates authoritative result storage from the solver core.
+class ResultsWriter {
+ public:
+  virtual ~ResultsWriter() = default;
+
+  /// @brief Writes one complete validated analysis state.
+  /// @return Success only after backend-specific finalization completes.
+  virtual Status Write(const std::filesystem::path& output_path,
+                       const Domain& domain, const AnalysisState& state,
+                       const std::vector<Diagnostic>& diagnostics) = 0;
+};
+
+}  // namespace fesa
+
+#endif  // FESA_RESULTS_RESULTS_WRITER_H_