Add wake word to xmini-c3 (#730)

* esp-hi: MCP protocol is not ready yet

* Add wake word to xmini-c3

main/audio_processing/afe_wake_word.h

@@ -0,0 +1,59 @@
+#ifndef AFE_WAKE_WORD_H
+#define AFE_WAKE_WORD_H
+
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+#include <freertos/event_groups.h>
+
+#include <esp_afe_sr_models.h>
+#include <esp_nsn_models.h>
+
+#include <list>
+#include <string>
+#include <vector>
+#include <functional>
+#include <mutex>
+#include <condition_variable>
+
+#include "audio_codec.h"
+#include "wake_word.h"
+
+class AfeWakeWord : public WakeWord {
+public:
+    AfeWakeWord();
+    ~AfeWakeWord();
+
+    void Initialize(AudioCodec* codec);
+    void Feed(const std::vector<int16_t>& data);
+    void OnWakeWordDetected(std::function<void(const std::string& wake_word)> callback);
+    void StartDetection();
+    void StopDetection();
+    bool IsDetectionRunning();
+    size_t GetFeedSize();
+    void EncodeWakeWordData();
+    bool GetWakeWordOpus(std::vector<uint8_t>& opus);
+    const std::string& GetLastDetectedWakeWord() const { return last_detected_wake_word_; }
+
+private:
+    esp_afe_sr_iface_t* afe_iface_ = nullptr;
+    esp_afe_sr_data_t* afe_data_ = nullptr;
+    char* wakenet_model_ = NULL;
+    std::vector<std::string> wake_words_;
+    EventGroupHandle_t event_group_;
+    std::function<void(const std::string& wake_word)> wake_word_detected_callback_;
+    AudioCodec* codec_ = nullptr;
+    std::string last_detected_wake_word_;
+
+    TaskHandle_t wake_word_encode_task_ = nullptr;
+    StaticTask_t wake_word_encode_task_buffer_;
+    StackType_t* wake_word_encode_task_stack_ = nullptr;
+    std::list<std::vector<int16_t>> wake_word_pcm_;
+    std::list<std::vector<uint8_t>> wake_word_opus_;
+    std::mutex wake_word_mutex_;
+    std::condition_variable wake_word_cv_;
+
+    void StoreWakeWordData(const int16_t* data, size_t size);
+    void AudioDetectionTask();
+};
+
+#endif