[PM-11406] Account Management: Prevent a verified user from deleting their account (#4878)

* 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

src/Core/Services/IMailService.cs

@@ -18,6 +18,7 @@ public interface IMailService
         ProductTierType productTier,
         IEnumerable<ProductType> products);
     Task SendVerifyDeleteEmailAsync(string email, Guid userId, string token);
+    Task SendCannotDeleteManagedAccountEmailAsync(string email);
     Task SendChangeEmailAlreadyExistsEmailAsync(string fromEmail, string toEmail);
     Task SendChangeEmailEmailAsync(string newEmailAddress, string token);
     Task SendTwoFactorEmailAsync(string email, string token);