fix(cutover): terminate detached launcher parent

apps/api/src/cutover-orchestrator.ts

@@ -163,7 +163,7 @@ export const nodeCutoverSystem: CutoverSystem = {
       '/usr/bin/python3',
       [
         '-c',
-        'import os,sys; pid=os.fork(); pid and (print(pid, flush=True) or os._exit(0)); os.setsid(); fd=os.open(os.devnull, os.O_RDWR); os.dup2(fd,0); os.dup2(fd,1); os.dup2(fd,2); os.close(fd) if fd>2 else None; os.execve(sys.argv[1], sys.argv[1:], dict(os.environ))',
+        "import os,sys; pid=os.fork(); (os.write(1,(str(pid)+'\\n').encode()) and os._exit(0)) if pid else (os.setsid(), (lambda fd:(os.dup2(fd,0),os.dup2(fd,1),os.dup2(fd,2),os.close(fd) if fd>2 else None))(os.open(os.devnull,os.O_RDWR)), os.execve(sys.argv[1],sys.argv[1:],dict(os.environ)))",
         ...argv,
       ],
       {