v1.9.0

Added

• App-relative logo resolution — branding logos configured as relative paths (e.g. /images/logo.png) are now resolved to absolute URLs at render time via BrandingSettings::resolvedLogo(), so they display in email clients. Absolute URLs, protocol-relative URLs, and data URIs pass through unchanged (#19, thanks @mrsafalpiya)

Fixed

• Button and other custom blocks were replaced with plain text when a template was loaded into the Compose Email editor, and were missing from the sent email. EmailTemplate::render() gained a renderBlocks flag so blocks round-trip in the editor, and TemplateMail now expands blocks in overridden bodies (#17, thanks @mrsafalpiya)
• Templates without an assigned theme now fall back to the user-configured default theme instead of the package's hardcoded colors — in the preview, the body infolist, and the sent email. New helpers: EmailTheme::resolvedDefaultColors() and EmailTemplate::resolvedThemeColors() (#18, thanks @mrsafalpiya)
• Theme colors stored as null or an empty string (cleared ColorPickers) no longer override the hardcoded defaults when resolving colors

Full Changelog: v1.8.1...v1.9.0