fix: reduce main loop sleep to 1ms and add polling in tests

Co-authored-by: aider (deepseek/deepseek-reasoner) <aider@aider.chat>

src/main.c

@@ -51,9 +51,9 @@ int main(int argc, char *argv[]) {
   while (1) {
     looper_process_commands(client);
     {
-      struct timespec ts = {.tv_sec = 0, .tv_nsec = 50000000};
+      struct timespec ts = {.tv_sec = 0, .tv_nsec = 1000000};
       nanosleep(&ts, NULL);
-    } /* check commands every 50 ms */
+    } /* check commands every 1 ms */
   }
 
   jack_client_close(client);