fix(frontend): preserve callback recovery state

frontend/src/views/auth/__tests__/WechatCallbackView.spec.ts

@@ -517,6 +517,50 @@ describe('WechatCallbackView', () => {
     expect(replaceMock).toHaveBeenCalledWith('/subscriptions')
   })
 
+  it('keeps the oauth flow active when complete-registration returns another pending step', async () => {
+    exchangePendingOAuthCompletionMock.mockResolvedValue({
+      error: 'invitation_required',
+      redirect: '/dashboard',
+      adoption_required: true,
+      suggested_display_name: 'WeChat Nick',
+      suggested_avatar_url: 'https://cdn.example/wechat.png',
+    })
+    completeWeChatOAuthRegistrationMock.mockResolvedValue({
+      auth_result: 'pending_session',
+      step: 'choose_account_action_required',
+      redirect: '/dashboard',
+      email: 'fresh@example.com',
+      resolved_email: 'fresh@example.com',
+      force_email_on_signup: true,
+      adoption_required: true,
+    })
+
+    const wrapper = mount(WechatCallbackView, {
+      global: {
+        stubs: {
+          AuthLayout: { template: '<div><slot /></div>' },
+          Icon: true,
+          RouterLink: { template: '<a><slot /></a>' },
+          transition: false,
+        },
+      },
+    })
+
+    await flushPromises()
+    await wrapper.find('input[type="text"]').setValue('invite-code')
+    await wrapper.find('button').trigger('click')
+    await flushPromises()
+
+    expect(completeWeChatOAuthRegistrationMock).toHaveBeenCalledWith('invite-code', {
+      adoptDisplayName: true,
+      adoptAvatar: true,
+    })
+    expect(setTokenMock).not.toHaveBeenCalled()
+    expect(replaceMock).not.toHaveBeenCalled()
+    expect(wrapper.get('[data-testid="wechat-choice-bind-existing"]').exists()).toBe(true)
+    expect(wrapper.get('[data-testid="wechat-choice-create-account"]').exists()).toBe(true)
+  })
+
   it('offers existing-account email collection during invitation flow', async () => {
     exchangePendingOAuthCompletionMock.mockResolvedValue({
       error: 'invitation_required',