feat: create stalwart module (#418)

- add stalwart module
- add psql database on the shared patroni instance
- add ceph-rgw credentials to eyaml
- ensure psql pass and s3 access key are converted to sensitive

Reviewed-on: #418

hieradata/roles/infra/mail/backend.yaml

@@ -0,0 +1,39 @@
+---
+hiera_include:
+  - stalwart
+  - profiles::sql::postgresdb
+
+# additional altnames
+profiles::pki::vault::alt_names:
+  - mail.main.unkin.net
+  - imap.main.unkin.net
+
+# manage a pgsql database + user
+profiles::sql::postgresdb::cluster_name: "patroni-shared-%{facts.environment}"
+profiles::sql::postgresdb::dbname: stalwart
+profiles::sql::postgresdb::dbuser: stalwart
+
+
+# Cluster role for node discovery
+stalwart::cluster_role: "%{facts.enc_role}"
+
+# PostgreSQL connection
+stalwart::postgresql_host: "master.%{hiera('profiles::sql::postgresdb::cluster_name')}.service.%{facts.country}-%{facts.region}.consul"
+stalwart::postgresql_database: "%{hiera('profiles::sql::postgresdb::dbname')}"
+stalwart::postgresql_user: "%{hiera('profiles::sql::postgresdb::dbuser')}"
+stalwart::postgresql_password: "%{hiera('profiles::sql::postgresdb::dbpass')}"
+
+# S3/Ceph-RGW connection
+stalwart::s3_endpoint: 'https://radosgw.service.consul'
+stalwart::s3_bucket: 'stalwart-maildata'
+stalwart::s3_region: "%{facts.region}"
+
+# Domains and relay
+stalwart::domains:
+  - 'mail.unkin.net'
+stalwart::postfix_relay_host: 'out-mta.main.unkin.net'
+stalwart::manage_dns_records: true   # DNS records point to individual servers
+
+## With load balancer:
+#stalwart::manage_dns_records: true
+#stalwart::loadbalancer_host: 'mail-lb.example.com'