Add C++ runtime for speech enhancement GTCRN models (#1977)

See also https://github.com/Xiaobin-Rong/gtcrn

sherpa-onnx/csrc/offline-speech-denoiser-gtcrn-model-config.h

@@ -0,0 +1,24 @@
+// sherpa-onnx/csrc/offline-speech-denoiser-gtcrn-model-config.h
+//
+// Copyright (c)  2025  Xiaomi Corporation
+#ifndef SHERPA_ONNX_CSRC_OFFLINE_SPEECH_DENOISER_GTCRN_MODEL_CONFIG_H_
+#define SHERPA_ONNX_CSRC_OFFLINE_SPEECH_DENOISER_GTCRN_MODEL_CONFIG_H_
+
+#include <string>
+
+#include "sherpa-onnx/csrc/parse-options.h"
+
+namespace sherpa_onnx {
+
+struct OfflineSpeechDenoiserGtcrnModelConfig {
+  std::string model;
+
+  void Register(ParseOptions *po);
+  bool Validate() const;
+
+  std::string ToString() const;
+};
+
+}  // namespace sherpa_onnx
+
+#endif  // SHERPA_ONNX_CSRC_OFFLINE_SPEECH_DENOISER_GTCRN_MODEL_CONFIG_H_