[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/Core.Test/Billing/Payment/Queries/GetPaymentMethodQueryTests.cs

@@ -3,7 +3,6 @@ using Bit.Core.Billing.Caches;
 using Bit.Core.Billing.Constants;
 using Bit.Core.Billing.Payment.Queries;
 using Bit.Core.Billing.Services;
-using Bit.Core.Services;
 using Bit.Core.Test.Billing.Extensions;
 using Braintree;
 using Microsoft.Extensions.Logging;
@@ -166,7 +165,7 @@ public class GetPaymentMethodQueryTests
         _setupIntentCache.GetSetupIntentIdForSubscriber(organization.Id).Returns("seti_123");
 
         _stripeAdapter
-            .SetupIntentGet("seti_123",
+            .GetSetupIntentAsync("seti_123",
                 Arg.Is<SetupIntentGetOptions>(options => options.HasExpansions("payment_method"))).Returns(
                 new SetupIntent
                 {