feat: update README, update configuration files for improved validation

group_vars/all/main.yml

@@ -11,6 +11,7 @@ base_packages_common:
   - rsync
   - ssl-cert
   - sudo
+  - unzip
 
 docker_enabled: true
 bun_enabled: true
@@ -215,7 +216,7 @@ mailserver:
   service_group: docker
   path: /srv/mail
   compose_project_name: mailserver
-  image: ghcr.io/docker-mailserver/docker-mailserver:latest
+  image: ghcr.io/docker-mailserver/docker-mailserver:v15.1.0
   hostname: mail.twirre.io
   env:
     ENABLE_SPAMASSASSIN: "0"

group_vars/all/vault.example.yml

@@ -16,7 +16,9 @@ vault_gitea_internal_token: REPLACE_ME
 vault_gitea_lfs_jwt_secret: REPLACE_ME
 
 vault_mailserver_accounts: |
-  # account@example.com|supersecret
+  # One account per line: email|{SCHEME}hashed-password
+  # Example:
+  # account@example.com|{SHA512-CRYPT}$6$example-salt$example-hash
 
 vault_twirre_io_env: {}
 vault_twirre_me_env: {}