fix: rework stripe webhooks into idempotent subscription sync (#2977)

Replace per-event webhook handlers with a single sync function that
fetches the current state from Stripe and converges the local
subscription, claim, and organisation type.

- Create organisations upfront before checkout, restricted as
  "pending payment" until the first payment syncs
- Add rate-limited subscription sync route, triggered on checkout
  success so the UI doesn't wait on webhooks
- Surface pending payment state in banner, billing table, and limits

packages/ee/server-only/limits/server.ts

@@ -1,5 +1,6 @@
 import { IS_BILLING_ENABLED } from '@documenso/lib/constants/app';
 import { INTERNAL_CLAIM_ID } from '@documenso/lib/types/subscription';
+import { isOrganisationPendingPayment } from '@documenso/lib/utils/billing';
 import { prisma } from '@documenso/prisma';
 import { DocumentSource, EnvelopeType, SubscriptionStatus } from '@prisma/client';
 import { DateTime } from 'luxon';
@@ -69,6 +70,15 @@ export const getServerLimits = async ({ userId, teamId }: GetServerLimitsOptions
     };
   }
 
+  // Early return for organisations created ahead of a paid checkout that are still awaiting payment.
+  if (isOrganisationPendingPayment(organisation)) {
+    return {
+      quota: INACTIVE_PLAN_LIMITS,
+      remaining: INACTIVE_PLAN_LIMITS,
+      maximumEnvelopeItemCount,
+    };
+  }
+
   // Allow unlimited documents for users with an unlimited documents claim.
   // This also allows "free" claim users without subscriptions if they have this flag.
   if (organisation.organisationClaim.flags.unlimitedDocuments) {