Why, after shutting down all the carbiono CE 26.3 services on ubuntu 24.04.4 does /usr/bin/envoy continue to run (with 1 zombie following it around)?

Shutting down carbonio ce before downing the server.

root@mail1:/opt/zextras# systemctl stop carbonio.target
root@mail1:/opt/zextras# systemctl status carbonio.target
○ carbonio.target - Zextras Carbonio
Loaded: loaded ( removed link ; enabled; preset: enabled)
Active: inactive (dead) since Tue 2026-04-21 18:25:34 PDT; 11s ago
Docs: man:systemd.special(7)

Apr 20 18:13:50 mail1.kibro.com systemd[1]: Reached target carbonio.target - Zextras Carbonio.
Apr 21 18:25:34 mail1.kibro.com systemd[1]: Stopped target carbonio.target - Zextras Carbonio.

top - 18:40:10 up 1 day, 27 min, 1 user, load average: 0.02, 0.11, 0.45
Tasks: 294 total, 1 running, 292 sleeping, 0 stopped, 1 zombie

here is what I am talking about...
as an aside, the whole carbonio mesh thing seems to generate 26-29 zombie
processes at cold boot...

root@mail1:/opt/zextras# ps aux | awk '$8 ~ /^[Zz]/'
carboni+ 3733 0.0 0.0 0 0 ? Z Apr20 0:00 [consul] <defunct>
root@mail1:/opt/zextras# ps -o ppid= -p 3733
3200
root@mail1:/opt/zextras# ps aux | grep 3200 | grep -v root
carboni+ 3200 0.7 0.0 2398496 62096 ? Ssl Apr20 10:51 /usr/bin/envoy --config-path  removed link  --disable-hot-restart