feat: allow server-side PostHog init config overrides

Replace individual posthog_api_host/posthog_debug fields with a generic
posthog_config object in RemoteConfig that gets spread into the PostHog
init call, allowing any PostHog init parameter to be overridden from
the /api/features endpoint.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

global.d.ts

@@ -34,8 +34,7 @@ interface Window {
     ga_measurement_id?: string
     mixpanel_token?: string
     posthog_project_token?: string
-    posthog_api_host?: string
-    posthog_debug?: boolean
+    posthog_config?: Record<string, unknown>
     require_whitelist?: boolean
     subscription_required?: boolean
     max_upload_size?: number

src/platform/remoteConfig/types.ts

@@ -1,3 +1,5 @@
+import type { PostHogConfig } from 'posthog-js'
+
 import type { TelemetryEventName } from '@/platform/telemetry/types'
 
 /**
@@ -30,8 +32,7 @@ export type RemoteConfig = {
   ga_measurement_id?: string
   mixpanel_token?: string
   posthog_project_token?: string
-  posthog_api_host?: string
-  posthog_debug?: boolean
+  posthog_config?: Partial<PostHogConfig>
   subscription_required?: boolean
   server_health_alert?: ServerHealthAlert
   max_upload_size?: number

src/platform/telemetry/providers/cloud/PostHogTelemetryProvider.test.ts

@@ -40,8 +40,12 @@ vi.mock('@/composables/auth/useCurrentUser', () => ({
   })
 }))
 
+const mockRemoteConfig = vi.hoisted(
+  () => ({ value: null }) as { value: Record<string, unknown> | null }
+)
+
 vi.mock('@/platform/remoteConfig/remoteConfig', () => ({
-  remoteConfig: { value: null }
+  remoteConfig: mockRemoteConfig
 }))
 
 vi.mock('posthog-js', () => hoisted.mockPosthog)
@@ -61,6 +65,7 @@ function createProvider(
 describe('PostHogTelemetryProvider', () => {
   beforeEach(() => {
     vi.clearAllMocks()
+    mockRemoteConfig.value = null
     window.__CONFIG__ = {
       posthog_project_token: 'phc_test_token'
     } as typeof window.__CONFIG__
@@ -93,17 +98,22 @@ describe('PostHogTelemetryProvider', () => {
       )
     })
 
-    it('enables debug mode when posthog_debug is true in config', async () => {
-      window.__CONFIG__ = {
-        posthog_project_token: 'phc_test_token',
-        posthog_debug: true
-      } as typeof window.__CONFIG__
-      new PostHogTelemetryProvider()
+    it('applies posthog_config overrides from remote config', async () => {
+      mockRemoteConfig.value = {
+        posthog_config: {
+          debug: true,
+          api_host: 'https://custom.host.com'
+        }
+      }
+      createProvider()
       await vi.dynamicImportSettled()
 
       expect(hoisted.mockInit).toHaveBeenCalledWith(
         'phc_test_token',
-        expect.objectContaining({ debug: true })
+        expect.objectContaining({
+          debug: true,
+          api_host: 'https://custom.host.com'
+        })
       )
     })
 

src/platform/telemetry/providers/cloud/PostHogTelemetryProvider.ts

@@ -101,17 +101,16 @@ export class PostHogTelemetryProvider implements TelemetryProvider {
         void import('posthog-js')
           .then((posthogModule) => {
             this.posthog = posthogModule.default
+            const serverConfig = remoteConfig.value?.posthog_config ?? {}
             this.posthog!.init(apiKey, {
-              api_host:
-                window.__CONFIG__?.posthog_api_host || 'https://t.comfy.org',
+              api_host: 'https://t.comfy.org',
               ui_host: 'https://us.posthog.com',
               autocapture: false,
               capture_pageview: false,
               capture_pageleave: false,
               persistence: 'localStorage+cookie',
-              debug:
-                window.__CONFIG__?.posthog_debug ??
-                import.meta.env.VITE_POSTHOG_DEBUG === 'true'
+              debug: import.meta.env.VITE_POSTHOG_DEBUG === 'true',
+              ...serverConfig
             })
             this.isInitialized = true
             this.flushEventQueue()