* Add check for managed user before purging account
* Rename IOrganizationRepository.GetByClaimedUserDomainAsync to GetByVerifiedUserEmailDomainAsync and refactor to return a list. Remove ManagedByOrganizationId from ProfileResponseMode. Add ManagesActiveUser to ProfileOrganizationResponseModel
* Rename the property ManagesActiveUser to UserIsManagedByOrganization
* Remove whole class #nullable enable and add it to specific places
* [PM-11405] Account Deprovisioning: Prevent a verified user from changing their email address
* Remove unnecessary .ToList()
* Refactor IUserService methods GetOrganizationsManagingUserAsync and IsManagedByAnyOrganizationAsync to not return nullable objects. Update ProfileOrganizationResponseModel.UserIsManagedByOrganization to not be nullable
* Prevent deletion of accounts managed by an organization when Account Deprovisioning is enabled
* Add CannotDeleteManagedAccountViewModel and email templates
- Added CannotDeleteManagedAccountViewModel class to handle emails related to preventing deletion of accounts managed by an organization.
- Added HTML and text email templates for sending notifications about the inability to delete an account owned by an organization.
- Updated IMailService interface with a new method to send the cannot delete managed account email.
- Implemented the SendCannotDeleteManagedAccountEmailAsync method in HandlebarsMailService.
- Added a check in UserService to send the cannot delete managed account email if the user is managed by any organization.
- Added a no-op implementation for SendCannotDeleteManagedAccountEmailAsync in NoopMailService.
* Update error message when unable to purge vault for managed account
* Update error message when unable to change email for managed account
* Update error message when unable to delete account when managed by organization
* Update error message in test for deleting organization-owned accounts
