add postgresql role

ansible/roles/postgresql/files/postgresql.service

@@ -0,0 +1,17 @@
+[Unit]
+Description=PostgreSQL database server
+Documentation=man:postgres(1)
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=notify
+User=postgres
+ExecStart=/usr/lib/postgresql/16/bin/pg_ctl start -D /etc/postgresql/16/main/
+ExecReload=/bin/kill -HUP $MAINPID
+KillMode=mixed
+KillSignal=SIGINT
+TimeoutSec=infinity
+
+[Install]
+WantedBy=multi-user.target