Align Postfix identity with system hostname on PMG nodes.

Add an idempotent baseline step that enforces myhostname/mydomain from hostname -f and reloads postfix only when drift is detected.

Co-authored-by: Cursor <cursoragent@cursor.com>

pmg/pmg_baseline.sls

@@ -17,6 +17,21 @@ pmg-cluster-status:
   cmd.run:
     - name: pmgcm status
 
+pmg-postfix-identity-from-system-hostname:
+  cmd.run:
+    - name: >-
+        HN="$(hostname -f)" &&
+        DM="${HN#*.}" &&
+        postconf -e "myhostname=${HN}" "mydomain=${DM}" &&
+        systemctl reload postfix
+    - unless: >-
+        HN="$(hostname -f)" &&
+        DM="${HN#*.}" &&
+        [ "$(postconf -h myhostname)" = "${HN}" ] &&
+        [ "$(postconf -h mydomain)" = "${DM}" ]
+    - require:
+      - service: pmg-service-postfix
+
 {% if manage_hosts_file %}
 pmg-managed-hosts:
   file.blockreplace: