v1.8.0: Audio 代码重构与低功耗优化 (#943)

* Reconstruct Audio Code

* Remove old IoT implementation

* Add MQTT-UDP documentation

* OTA升级失败时，可以继续使用

main/boards/esp-sparkbot/esp_sparkbot_board.cc

@@ -1,5 +1,5 @@
 #include "wifi_board.h"
-#include "audio_codecs/es8311_audio_codec.h"
+#include "codecs/es8311_audio_codec.h"
 #include "display/lcd_display.h"
 #include "font_awesome_symbols.h"
 #include "application.h"