* update reset thumbnail feature
* fix the Translation issues
* centralize thumbnail ext logic and use site config API
* drop reset API; use PATCH metadata and reload only selected thumbnails
* Improve handling of resetting thumbnails
* Remove unused code
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Co-authored-by: Aaron Liu <abslant.liu@gmail.com>
* feat(email): auto switch for existing language templates
* feat(email): use friendly lang display name
* fix(email): prevent infinite loop when updating templates
* feat(email): adjust email template order by drag-and-drop
* revoke(email): remove drag-and-drop for email template order
* feat(email): support magic variables in email title
* feat(email): add preferred language setting in email template editor