feat: Add sample file for Podman systemd.

docs/deploying/podman-systemd.md

@@ -0,0 +1,16 @@
+# tuwunel in Podman systemd
+
+Copy [tuwunel.container](tuwunel.container) to ~/.config/containers/systemd/tuwunel.container.
+Reload daemon:
+```
+systemctl --user daemon-reload
+```
+Start the service:
+```
+systemctl --user start tuwunel
+```
+
+To check the logs, run:
+```
+journalctl -eu tuwunel.container --user
+```