add session cookie auth on cloud dist (#6295)

## Summary

Implemented cookie-based session authentication for cloud distribution,
replacing service worker approach with extension-based lifecycle hooks.

## Changes

- **What**: Added session cookie management via [extension
hooks](https://docs.comfy.org/comfyui/extensions) for login, token
refresh, and logout events
- **Architecture**: DDD-compliant structure with platform layer
(`src/platform/auth/session/`) and cloud-gated extension
- **New Extension Hooks**: `onAuthTokenRefreshed()` and
`onAuthUserLogout()` in [ComfyExtension
interface](src/types/comfy.ts:220-232)

```mermaid
sequenceDiagram
    participant User
    participant Firebase
    participant Extension
    participant Backend

    User->>Firebase: Login
    Firebase->>Extension: onAuthUserResolved
    Extension->>Backend: POST /auth/session (with JWT)
    Backend-->>Extension: Set-Cookie

    Firebase->>Firebase: Token Refresh
    Firebase->>Extension: onAuthTokenRefreshed
    Extension->>Backend: POST /auth/session (with new JWT)
    Backend-->>Extension: Update Cookie

    User->>Firebase: Logout
    Firebase->>Extension: onAuthUserLogout (user null)
    Extension->>Backend: DELETE /auth/session
    Backend-->>Extension: Clear Cookie
```

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-6295-add-session-cookie-auth-on-cloud-dist-2986d73d365081868c56e5be1ad0d0d4)
by [Unito](https://www.unito.io)

src/stores/firebaseAuthStore.ts

@@ -8,6 +8,7 @@ import {
   deleteUser,
   getAdditionalUserInfo,
   onAuthStateChanged,
+  onIdTokenChanged,
   sendPasswordResetEmail,
   setPersistence,
   signInWithEmailAndPassword,
@@ -61,6 +62,9 @@ export const useFirebaseAuthStore = defineStore('firebaseAuth', () => {
   const balance = ref<GetCustomerBalanceResponse | null>(null)
   const lastBalanceUpdateTime = ref<Date | null>(null)
 
+  // Token refresh trigger - increments when token is refreshed
+  const tokenRefreshTrigger = ref(0)
+
   // Providers
   const googleProvider = new GoogleAuthProvider()
   googleProvider.addScope('email')
@@ -95,6 +99,13 @@ export const useFirebaseAuthStore = defineStore('firebaseAuth', () => {
     lastBalanceUpdateTime.value = null
   })
 
+  // Listen for token refresh events
+  onIdTokenChanged(auth, (user) => {
+    if (user && isCloud) {
+      tokenRefreshTrigger.value++
+    }
+  })
+
   const getIdToken = async (): Promise<string | undefined> => {
     if (!currentUser.value) return
     try {
@@ -421,6 +432,7 @@ export const useFirebaseAuthStore = defineStore('firebaseAuth', () => {
     balance,
     lastBalanceUpdateTime,
     isFetchingBalance,
+    tokenRefreshTrigger,
 
     // Getters
     isAuthenticated,