feat: integrate Impact telemetry with checkout attribution for subscriptions (#8688)

Implement Impact telemetry and checkout attribution through cloud
subscription checkout flows.

This PR adds Impact.com tracking support and carries attribution context
from landing-page visits into subscription checkout requests so
conversion attribution can be validated end-to-end.

- Register a new `ImpactTelemetryProvider` during cloud telemetry
initialization.
- Initialize the Impact queue/runtime (`ire`) and load the Universal
Tracking Tag script once.
- Invoke `ire('identify', ...)` on page views with dynamic `customerId`
and SHA-1 `customerEmail` (or empty strings when unknown).
- Expand checkout attribution capture to include `im_ref`, UTM fields,
and Google click IDs, with local persistence across navigation.
- Attempt `ire('generateClickId')` with a timeout and fall back to
URL/local attribution when unavailable.
- Include attribution payloads in checkout creation requests for both:
  - `/customers/cloud-subscription-checkout`
  - `/customers/cloud-subscription-checkout/{tier}`
- Extend begin-checkout telemetry metadata typing to include attribution
fields.
- Add focused unit coverage for provider behavior, attribution
persistence/fallback logic, and checkout request payloads.

Tradeoffs / constraints:
- Attribution collection is treated as best-effort in tiered checkout
flow to avoid blocking purchases.
- Backend checkout handlers must accept and process the additional JSON
attribution fields.

## Screenshots

<img width="908" height="208" alt="image"
src="https://github.com/user-attachments/assets/03c16d60-ffda-40c9-9bd6-8914d841be50"/>
<img width="1144" height="460" alt="image"
src="https://github.com/user-attachments/assets/74b97fde-ce0a-43e6-838e-9a4aba484488"/>
<img width="1432" height="320" alt="image"
src="https://github.com/user-attachments/assets/30c22a9f-7bd8-409f-b0ef-e4d02343780a"/>
<img width="341" height="135" alt="image"
src="https://github.com/user-attachments/assets/f6d918ae-5f80-45e0-855a-601abea61dec"/>

src/platform/cloud/subscription/utils/subscriptionCheckoutUtil.test.ts

@@ -22,6 +22,10 @@ const {
     ga_client_id: 'ga-client-id',
     ga_session_id: 'ga-session-id',
     ga_session_number: 'ga-session-number',
+    im_ref: 'impact-click-123',
+    utm_source: 'impact',
+    utm_medium: 'affiliate',
+    utm_campaign: 'spring-launch',
     gclid: 'gclid-123',
     gbraid: 'gbraid-456',
     wbraid: 'wbraid-789'
@@ -54,6 +58,14 @@ vi.mock('@/platform/telemetry/utils/checkoutAttribution', () => ({
 
 global.fetch = vi.fn()
 
+type Distribution = 'desktop' | 'localhost' | 'cloud'
+
+const setDistribution = (distribution: Distribution) => {
+  ;(
+    globalThis as typeof globalThis & { __DISTRIBUTION__: Distribution }
+  ).__DISTRIBUTION__ = distribution
+}
+
 function createDeferred<T>() {
   let resolve: (value: T) => void = () => {}
   const promise = new Promise<T>((res) => {
@@ -65,6 +77,7 @@ function createDeferred<T>() {
 
 describe('performSubscriptionCheckout', () => {
   beforeEach(() => {
+    setDistribution('cloud')
     vi.clearAllMocks()
     mockIsCloud.value = true
     mockUserId.value = 'user-123'
@@ -72,6 +85,7 @@ describe('performSubscriptionCheckout', () => {
 
   afterEach(() => {
     vi.restoreAllMocks()
+    setDistribution('localhost')
   })
 
   it('tracks begin_checkout with user id and tier metadata', async () => {
@@ -93,6 +107,10 @@ describe('performSubscriptionCheckout', () => {
       ga_client_id: 'ga-client-id',
       ga_session_id: 'ga-session-id',
       ga_session_number: 'ga-session-number',
+      im_ref: 'impact-click-123',
+      utm_source: 'impact',
+      utm_medium: 'affiliate',
+      utm_campaign: 'spring-launch',
       gclid: 'gclid-123',
       gbraid: 'gbraid-456',
       wbraid: 'wbraid-789'
@@ -107,6 +125,10 @@ describe('performSubscriptionCheckout', () => {
           ga_client_id: 'ga-client-id',
           ga_session_id: 'ga-session-id',
           ga_session_number: 'ga-session-number',
+          im_ref: 'impact-click-123',
+          utm_source: 'impact',
+          utm_medium: 'affiliate',
+          utm_campaign: 'spring-launch',
           gclid: 'gclid-123',
           gbraid: 'gbraid-456',
           wbraid: 'wbraid-789'
@@ -116,6 +138,41 @@ describe('performSubscriptionCheckout', () => {
     expect(openSpy).toHaveBeenCalledWith(checkoutUrl, '_blank')
   })
 
+  it('continues checkout when attribution collection fails', async () => {
+    const checkoutUrl = 'https://checkout.stripe.com/test'
+    const openSpy = vi.spyOn(window, 'open').mockImplementation(() => null)
+    const warnSpy = vi.spyOn(console, 'warn').mockImplementation(() => {})
+
+    mockGetCheckoutAttribution.mockRejectedValueOnce(
+      new Error('Attribution failed')
+    )
+    vi.mocked(global.fetch).mockResolvedValue({
+      ok: true,
+      json: async () => ({ checkout_url: checkoutUrl })
+    } as Response)
+
+    await performSubscriptionCheckout('pro', 'monthly', true)
+
+    expect(warnSpy).toHaveBeenCalledWith(
+      '[SubscriptionCheckout] Failed to collect checkout attribution',
+      expect.any(Error)
+    )
+    expect(global.fetch).toHaveBeenCalledWith(
+      expect.stringContaining('/customers/cloud-subscription-checkout/pro'),
+      expect.objectContaining({
+        method: 'POST',
+        body: JSON.stringify({})
+      })
+    )
+    expect(mockTelemetry.trackBeginCheckout).toHaveBeenCalledWith({
+      user_id: 'user-123',
+      tier: 'pro',
+      cycle: 'monthly',
+      checkout_type: 'new'
+    })
+    expect(openSpy).toHaveBeenCalledWith(checkoutUrl, '_blank')
+  })
+
   it('uses the latest userId when it changes after checkout starts', async () => {
     const checkoutUrl = 'https://checkout.stripe.com/test'
     const openSpy = vi.spyOn(window, 'open').mockImplementation(() => null)

src/platform/cloud/subscription/utils/subscriptionCheckoutUtil.ts

@@ -4,11 +4,11 @@ import { getComfyApiBaseUrl } from '@/config/comfyApi'
 import { t } from '@/i18n'
 import { isCloud } from '@/platform/distribution/types'
 import { useTelemetry } from '@/platform/telemetry'
-import { getCheckoutAttribution } from '@/platform/telemetry/utils/checkoutAttribution'
 import {
   FirebaseAuthStoreError,
   useFirebaseAuthStore
 } from '@/stores/firebaseAuthStore'
+import type { CheckoutAttributionMetadata } from '@/platform/telemetry/types'
 import type { TierKey } from '@/platform/cloud/subscription/constants/tierPricing'
 import type { BillingCycle } from './subscriptionTierRank'
 
@@ -19,6 +19,18 @@ const getCheckoutTier = (
   billingCycle: BillingCycle
 ): CheckoutTier => (billingCycle === 'yearly' ? `${tierKey}-yearly` : tierKey)
 
+const getCheckoutAttributionForCloud =
+  async (): Promise<CheckoutAttributionMetadata> => {
+    if (__DISTRIBUTION__ !== 'cloud') {
+      return {}
+    }
+
+    const { getCheckoutAttribution } =
+      await import('@/platform/telemetry/utils/checkoutAttribution')
+
+    return getCheckoutAttribution()
+  }
+
 /**
  * Core subscription checkout logic shared between PricingTable and
  * SubscriptionRedirectView. Handles:
@@ -49,7 +61,15 @@ export async function performSubscriptionCheckout(
   }
 
   const checkoutTier = getCheckoutTier(tierKey, currentBillingCycle)
-  const checkoutAttribution = getCheckoutAttribution()
+  let checkoutAttribution: CheckoutAttributionMetadata = {}
+  try {
+    checkoutAttribution = await getCheckoutAttributionForCloud()
+  } catch (error) {
+    console.warn(
+      '[SubscriptionCheckout] Failed to collect checkout attribution',
+      error
+    )
+  }
   const checkoutPayload = { ...checkoutAttribution }
 
   const response = await fetch(