Add the jarld.service alias for jarl.service

systemctl restart/status jarld now work too. The package relinks a unit
enabled by an older version on upgrade, so the alias appears without
re-enabling; make uninstall removes the link.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

deploy/systemd/jarl.service

@@ -65,3 +65,5 @@ SystemCallErrorNumber=EPERM
 
 [Install]
 WantedBy=multi-user.target
+# 'systemctl restart jarld' works too (the daemon's binary is jarld).
+Alias=jarld.service