Improve mail config merging and logo URL resolution

[1.2.1] - 2026-01-24

Changed

• EmailChannel: Improved configuration loading to merge core mail settings from services.mail with extension-specific config.
  • Core framework mail settings now take precedence for mail transport configuration.
  • Allows centralized mail configuration in the main application while extension-specific settings remain customizable.
• EmailFormatter: Updated logo URL resolution to use global_variables from config.
  • Now reads from services.mail.templates.global_variables.logo_url for consistency with core framework.
  • Falls back to extension default if not configured.

Notes

• No breaking changes. Existing configurations continue to work.
• For centralized mail configuration, define settings in config/services.php under the mail key.