media: Increase buffer size to 14336 (28kb / 150ms)

This lets the playback be smooth even with apps with somewhat
heavy think functions or that draw with direct ctx and also
helps a bit when garbage collection kicks in.

components/st3m/st3m_media.h

@@ -4,7 +4,7 @@
 #include <stdbool.h>
 #include <stdint.h>
 
-#define AUDIO_BUF_SIZE (8192)
+#define AUDIO_BUF_SIZE (14336)
 
 typedef struct _st3m_media st3m_media;