**Enhancements**
* Tweak: Refactored group create/update forms.
** Improved avatar upload handling with better mime type filtering.
** Enhanced security with better input sanitization and validation.
** Deprecated unused variables and cleaned up formatting for better maintainability.
* Tweak: Removed ability to change the group role by the user (group manager role) itself.
**Bugfixes**
* Fixed: Misplaced `nl2br` calls to preserve content formatting. Moved the `nl2br` function call to ensure proper formatting of post content after embedding and auto-embedding processes.
* Fixed: Added User ID to the user card data for proper user actions in the members/invites group tabs.
**Templates required update**
* discussion/legacy/single.php
* discussion/new.php
* discussion/single.php
* tabs/avatar.php
* tabs/single-group-tabs.php
* create-group-form.php
