refactor: recreate profiles::postfix::gateway with parameterization

- refactor profiles::postfix::gateway as parameterized class
- move base postfix parameters, transports, and virtuals in hiera for deep merging
- convert SMTP restrictions to arrays for better readability using join()
- add postscreen enable/disable boolean with conditional master.cf configuration
- add per-domain TLS policy maps (smtp_tls_policy_maps/smtpd_tls_policy_maps)
- convert alias_maps to array parameter for flexibility

hieradata/roles/infra/mail/gateway.yaml

@@ -3,3 +3,33 @@
 # additional altnames
 profiles::pki::vault::alt_names:
   - in-mta.main.unkin.net
+
+# base postfix configuration (passed to postfix class)
+postfix::relayhost: 'direct'
+postfix::myorigin: 'main.unkin.net'
+postfix::mydestination: 'blank'
+postfix::mynetworks: '127.0.0.0/8 [::1]/128'
+postfix::mta: true
+postfix::manage_aliases: true
+
+# profile parameters for customization
+profiles::postfix::gateway::myhostname: 'in-mta.main.unkin.net'
+
+# postfix transports
+postfix::transports:
+  'main.unkin.net':
+    ensure: present
+    destination: 'relay'
+    nexthop: 'ausyd1nxvm2120.main.unkin.net:25'
+
+# postfix virtuals
+postfix::virtuals:
+  'root':
+    ensure: present
+    destination: 'ben@main.unkin.net'
+  'postmaster':
+    ensure: present
+    destination: 'ben@main.unkin.net'
+  'abuse':
+    ensure: present
+    destination: 'ben@main.unkin.net'