feat(thermal): publish fully validated HDF5 histories atomically

include/fesa/io/hdf5/thermal_hdf5_results_writer.h

@@ -0,0 +1,19 @@
+#ifndef FESA_IO_HDF5_THERMAL_HDF5_RESULTS_WRITER_H_
+#define FESA_IO_HDF5_THERMAL_HDF5_RESULTS_WRITER_H_
+
+#include "fesa/results/thermal_results_writer.h"
+
+namespace fesa {
+/// @brief Writes schema-v1 shell transient-heat results after closed-file
+/// validation.
+class ThermalHdf5ResultsWriter final : public ThermalResultsWriter {
+ public:
+  /// @brief Writes the complete schema-v1 thermal artifact without replacing a
+  /// prior final file until closed-file validation succeeds.
+  Status Write(const std::filesystem::path& output_path, const Domain& domain,
+               const ThermalAnalysisState& state,
+               const std::vector<Diagnostic>& diagnostics) override;
+};
+}  // namespace fesa
+
+#endif  // FESA_IO_HDF5_THERMAL_HDF5_RESULTS_WRITER_H_