refactor: recreate profiles::postfix::gateway with parameterization and templates (#416)

- refactor profiles::postfix::gateway as parameterized class
- move base postfix parameters, transports, and virtuals to hiera for flexibility
- 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)
- convert alias_maps to array parameter for flexibility
- convert all postfix map files to ERB templates with parameter hashes
- add map parameters: sender_canonical_maps, sender_access_maps, relay_recipients_maps,
  relay_domains_maps, recipient_canonical_maps, recipient_access_maps, postscreen_access_maps, helo_access_maps
- move default map data to hiera while keeping parameters as empty hashes by default

This approach balances flexibility with data-driven configuration, allowing
easy customization through parameters while keeping transport/virtual maps
and default map data in hiera for role-specific overrides.

Reviewed-on: #416

hieradata/common.yaml

@@ -158,6 +158,15 @@ lookup_options:
   rke2::config_hash:
     merge:
       strategy: deep
+  postfix::configs:
+    merge:
+      strategy: deep
+  postfix::maps:
+    merge:
+      strategy: deep
+  postfix::virtuals:
+    merge:
+      strategy: deep
 
 facts_path: '/opt/puppetlabs/facter/facts.d'
 

hieradata/roles/infra/mail/gateway.yaml

@@ -3,3 +3,50 @@
 # 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 map content (templates)
+profiles::postfix::gateway::relay_recipients_maps:
+  '@main.unkin.net': 'OK'
+
+profiles::postfix::gateway::relay_domains_maps:
+  'main.unkin.net': 'OK'
+
+profiles::postfix::gateway::postscreen_access_maps:
+  '127.0.0.1/32': 'permit'
+  '10.10.12.200/32': 'permit'
+
+profiles::postfix::gateway::helo_access_maps:
+  '.dynamic.': 'REJECT'
+  '.dialup.': 'REJECT'
+  'unknown': 'REJECT'
+  'localhost': 'REJECT You are not localhost'
+
+# 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'