[PM-24616] refactor stripe adapter (#6527)

* move billing services+tests to billing namespaces

* reorganized methods in file and added comment headers

* renamed StripeAdapter methods for better clarity

* clean up redundant qualifiers

* Upgrade Stripe.net to v48.4.0

* Update PreviewTaxAmountCommand

* Remove unused UpcomingInvoiceOptionExtensions

* Added SubscriptionExtensions with GetCurrentPeriodEnd

* Update PremiumUserBillingService

* Update OrganizationBillingService

* Update GetOrganizationWarningsQuery

* Update BillingHistoryInfo

* Update SubscriptionInfo

* Remove unused Sql Billing folder

* Update StripeAdapter

* Update StripePaymentService

* Update InvoiceCreatedHandler

* Update PaymentFailedHandler

* Update PaymentSucceededHandler

* Update ProviderEventService

* Update StripeEventUtilityService

* Update SubscriptionDeletedHandler

* Update SubscriptionUpdatedHandler

* Update UpcomingInvoiceHandler

* Update ProviderSubscriptionResponse

* Remove unused Stripe Subscriptions Admin Tool

* Update RemoveOrganizationFromProviderCommand

* Update ProviderBillingService

* Update RemoveOrganizatinoFromProviderCommandTests

* Update PreviewTaxAmountCommandTests

* Update GetCloudOrganizationLicenseQueryTests

* Update GetOrganizationWarningsQueryTests

* Update StripePaymentServiceTests

* Update ProviderBillingControllerTests

* Update ProviderEventServiceTests

* Update SubscriptionDeletedHandlerTests

* Update SubscriptionUpdatedHandlerTests

* Resolve Billing test failures

I completely removed tests for the StripeEventService as they were using a system I setup a while back that read JSON files of the Stripe event structure. I did not anticipate how frequently these structures would change with each API version and the cost of trying to update these specific JSON files to test a very static data retrieval service far outweigh the benefit.

* Resolve Core test failures

* Run dotnet format

* Remove unused provider migration

* Fixed failing tests

* Run dotnet format

* Replace the old webhook secret key with new one (#6223)

* Fix compilation failures in additions

* Run dotnet format

* Bump Stripe API version

* Fix recent addition: CreatePremiumCloudHostedSubscriptionCommand

* Fix new code in main according to Stripe update

* Fix InvoiceExtensions

* Bump SDK version to match API Version

* cleanup

* fixing items missed after the merge

* use expression body for all simple returns

* forgot fixes, format, and pr feedback

* claude pr feedback

* pr feedback and cleanup

* more claude feedback

---------

Co-authored-by: Alex Morask <amorask@bitwarden.com>
Co-authored-by: cyprain-okeke <108260115+cyprain-okeke@users.noreply.github.com>

test/Billing.Test/Controllers/BitPayControllerTests.cs

@@ -31,7 +31,7 @@ public class BitPayControllerTests
     private readonly IUserRepository _userRepository = Substitute.For<IUserRepository>();
     private readonly IProviderRepository _providerRepository = Substitute.For<IProviderRepository>();
     private readonly IMailService _mailService = Substitute.For<IMailService>();
-    private readonly IPaymentService _paymentService = Substitute.For<IPaymentService>();
+    private readonly IStripePaymentService _paymentService = Substitute.For<IStripePaymentService>();
 
     private readonly IPremiumUserBillingService _premiumUserBillingService =
         Substitute.For<IPremiumUserBillingService>();