Implement display, SD card, I2S WAV audio player, and button sync logic

sound_picture_app/Audio_Player.h

@@ -0,0 +1,18 @@
+#pragma once
+#include <Arduino.h>
+#include "FS.h"
+#include "SD_Card.h"
+
+// Define I2S Pins for external DAC (MAX98357A, etc.)
+#define I2S_BCLK      1
+#define I2S_LRCK      2
+#define I2S_DIN       4
+
+void playWav(const char* filePath);
+void stopWav();
+bool isWavPlaying();
+
+void Search_Wavs(const char* directory);
+extern uint16_t Wav_Count;
+extern char Wav_Names[100][100];
+