feat: add v2 task control and asynchronous isolated workers

src/os_win.c

@@ -618,6 +618,7 @@ int os_run_capture_token(const char *cwd, const char *const argv[],
           n == 0)
         break;
       os_cap_append(&buf, &len, &cap, max_out, tmp, n, &truncated);
+      os_observe_output(tmp, n);
       idle = 0;
     } else if (reaped) {
       Sleep(idle++ < 50 ? 1 : 20);