ilimination of system code, removal of x-watcher and replacement of it by dmon, fixes in audio code, dynamic asset reload

src/twn_audio_c.h

@@ -48,8 +48,7 @@ union AudioContext {
 typedef struct AudioChannel {
     AudioFileType file_type;
     union AudioContext context; /* interpreted by `file_type` value */
-    const char *path;
-    const char *name;
+    char *path;
     bool repeat;
     float volume;
     float panning;