Fix(cloud)/pricing annual misc (#7701)

## Summary

Fix: PricingTable showed "Current Plan" on the wrong billing cycle
(e.g., showing it on Yearly when subscribed to Monthly) because we
weren't checking subscription_duration. Now we check for ANNUAL |
MONTHLY match.

Fix: Subscribed users were being sent to billing portal instead of
checkout. Now routes to checkout.

Improved: Types now use openapi.yml as source of truth. Tier names in
user popover and subscription panels now reflect the billing cycle
(YEARLY/MONTHLY).

Recommended to merge this before
https://github.com/Comfy-Org/ComfyUI_frontend/pull/7692

---------

Co-authored-by: bymyself <cbyrne@comfy.org>

tests-ui/tests/platform/cloud/subscription/components/SubscriptionPanel.test.ts

@@ -12,6 +12,7 @@ const mockIsCancelled = ref(false)
 const mockSubscriptionTier = ref<
   'STANDARD' | 'CREATOR' | 'PRO' | 'FOUNDERS_EDITION' | null
 >('CREATOR')
+const mockIsYearlySubscription = ref(false)
 
 const TIER_TO_NAME: Record<string, string> = {
   STANDARD: 'Standard',
@@ -27,9 +28,12 @@ const mockSubscriptionData = {
   formattedRenewalDate: computed(() => '2024-12-31'),
   formattedEndDate: computed(() => '2024-12-31'),
   subscriptionTier: computed(() => mockSubscriptionTier.value),
-  subscriptionTierName: computed(() =>
-    mockSubscriptionTier.value ? TIER_TO_NAME[mockSubscriptionTier.value] : ''
-  ),
+  subscriptionTierName: computed(() => {
+    if (!mockSubscriptionTier.value) return ''
+    const baseName = TIER_TO_NAME[mockSubscriptionTier.value]
+    return mockIsYearlySubscription.value ? `${baseName} Yearly` : baseName
+  }),
+  isYearlySubscription: computed(() => mockIsYearlySubscription.value),
   handleInvoiceHistory: vi.fn()
 }
 
@@ -212,6 +216,7 @@ describe('SubscriptionPanel', () => {
     mockIsActiveSubscription.value = false
     mockIsCancelled.value = false
     mockSubscriptionTier.value = 'CREATOR'
+    mockIsYearlySubscription.value = false
   })
 
   describe('subscription state functionality', () => {