Feat: Add Organization Subscription-Preview Endpoint

[sbrown-livefront]

🎟️ Tracking

https://bitwarden.atlassian.net/browse/PM-39927

📔 Objective

First endpoint on the new Bit.Subscriptions.Organization feature library and first consumer of the shared, Stripe-invoice-preview–driven cart summary. Sources the organization's upcoming-renewal cart totals from an actual Stripe invoice preview instead of reconstructing them from local subscription state.

Adds:

• GetSubscriptionPreviewQuery (Bit.Invoicing) — shared, ISubscriber-generic query ported from GetBitwardenSubscriptionQuery. Resolves tier/cadence (collapsing TeamsStarter → Teams), previews via create_preview(subscription=id), falls back to the subscription overload when there's no upcoming invoice, and maps subscription status → SubscriptionPreview envelope (suspension/grace-period/cancel). Registered in AddInvoicing(). The Organization path is fully wired here; the User/Premium path is stubbed for Task 8.
• GET /organizations/{organizationId:guid}/billing/subscription/preview — new route on the org subscription group, gated behind PM36631_PreviewDrivenCart.
• Authorization via AuthorizeAttribute<OrganizationBillingRequirement> using the IOrganizationRequirement framework (Owner or confirmed provider-user-for-org; excludes Admin/Custom). Lives entirely in the OrganizationAuthorization library — no dependency on the Api project.
• Unit tests for the query, the requirement, and the endpoint handler + group wiring.

[codecov]

Codecov Report

❌ Patch coverage is 87.61905% with 13 lines in your changes missing coverage. Please review.
✅ Project coverage is 63.66%. Comparing base (7640e4b) to head (b15d8d0).

Files with missing lines	Patch %	Lines
...icePreviews/Queries/GetSubscriptionPreviewQuery.cs	85.54%	9 Missing and 3 partials ⚠️
...ion/OrganizationSubscriptionEndpointsExtensions.cs	80.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8245      +/-   ##
==========================================
+ Coverage   63.64%   63.66%   +0.02%     
==========================================
  Files        2430     2433       +3     
  Lines      104962   105067     +105     
  Branches     9506     9517      +11     
==========================================
+ Hits        66798    66896      +98     
- Misses      35868    35872       +4     
- Partials     2296     2299       +3     

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[github-actions]

🤖 Bitwarden Claude Code Review

Overall Assessment: APPROVE

Reviewed the new GetSubscriptionPreviewQuery in Bit.Invoicing, the GET .../billing/subscription/preview endpoint and handler in Bit.Subscriptions.Organization, the OrganizationBillingRequirement authorization path, and the AuthorizeAttribute<T> namespace move into the OrganizationAuthorization library. Traced authorization end to end: the group requires Policies.Application plus OrganizationBillingRequirement, and OrganizationRequirementHandler resolves the org from the same {organizationId:guid} route segment the host mounts, so there is no cross-org exposure; the handler 404s on both a missing organization and a subscriber with no Stripe subscription. Checked exception mapping (ConflictException → 409, NotFoundException → 404 via WithBasicExceptionHandling), DI lifetimes and TryAdd* usage, the invoice_upcoming_none fallback to the subscription projection, and confirmed the AuthorizeAttribute<T> move leaves no unmigrated references (remaining [Authorize<T>] mentions elsewhere are XML-doc comments, and ControllerAuthorizationTestHelpers matches by base type, not namespace). All eight prior review threads are resolved, and the only commits since the last round are merges from main; lock file churn is limited to propagating the new OrganizationAuthorization project reference, with no new NuGet packages.

Code Review Details

No new findings.

[BTreston]

Approved for AC changes

The base branch was changed.

[amorask-bitwarden]

Looks great, nice work.