fix: replace process pool with thread pool

soar_bus.py

@@ -180,7 +180,7 @@ if __name__ == "__main__":
         s.close()
 
     try:
-        with concurrent.futures.ProcessPoolExecutor() as executor:
+        with concurrent.futures.ThreadPoolExecutor(max_workers=20) as executor:
             main(executor)
     except KeyboardInterrupt:
         executor.shutdown(wait=False)