* feat: add sync functionality for OAuth providers
- Implemented `check_sync_enabled` method to verify if sync is enabled for Google, GitHub, GitLab, and Gitea.
- Added `sync_user_data` method to update user details, including first name, last name, display name, and avatar.
- Updated configuration variables to include sync options for each provider.
- Integrated sync check into the login/signup process.
* feat: add sync toggle for OAuth providers in configuration forms
* fix: remove default value for sync options in OAuth configuration forms
* chore: delete old avatar and upload a new one
* chore: update class method
* chore: add email nullable
* refactor: streamline sync check for multiple providers and improve avatar deletion logic
* fix: ensure ENABLE_SYNC configurations default to "0" for Gitea, Github, Gitlab, and Google forms
* fix: simplify toggle switch value handling in ControllerSwitch component
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Co-authored-by: b-saikrishnakanth <bsaikrishnakanth97@gmail.com>
sriram veeraghanta