fix(payment): restore upgrade-safe payment flows

frontend/src/views/user/__tests__/PaymentResultView.spec.ts

@@ -255,14 +255,21 @@ describe('PaymentResultView', () => {
     expect(window.localStorage.getItem(PAYMENT_RECOVERY_STORAGE_KEY)).toBeNull()
   })
 
-  it('does not fall back to public out_trade_no verification when resume_token recovery fails', async () => {
+  it('falls back to public out_trade_no verification when resume_token recovery fails in legacy return flows', async () => {
     routeState.query = {
       resume_token: 'resume-fail',
       out_trade_no: 'legacy-should-not-run',
       trade_status: 'TRADE_SUCCESS',
     }
     resolveOrderPublicByResumeToken.mockRejectedValueOnce(new Error('resume failed'))
-    mount(PaymentResultView, {
+    verifyOrderPublic.mockResolvedValueOnce({
+      data: {
+        ...orderFactory('PAID'),
+        out_trade_no: 'legacy-should-not-run',
+      },
+    })
+
+    const wrapper = mount(PaymentResultView, {
       global: {
         stubs: {
           OrderStatusBadge: true,
@@ -273,7 +280,9 @@ describe('PaymentResultView', () => {
     await flushPromises()
 
     expect(resolveOrderPublicByResumeToken).toHaveBeenCalledWith('resume-fail')
-    expect(verifyOrderPublic).not.toHaveBeenCalled()
+    expect(verifyOrderPublic).toHaveBeenCalledWith('legacy-should-not-run')
+    expect(pollOrderStatus).not.toHaveBeenCalled()
+    expect(wrapper.text()).toContain('payment.result.success')
   })
 
   it('ignores a stale global recovery snapshot when legacy return markers do not identify the order', async () => {

frontend/src/views/user/__tests__/PaymentView.spec.ts

@@ -252,6 +252,33 @@ describe('PaymentView WeChat JSAPI flow', () => {
     expect(window.localStorage.getItem(PAYMENT_RECOVERY_STORAGE_KEY)).toBeNull()
   })
 
+  it('clears stale recovery state when JSAPI never becomes available', async () => {
+    vi.useFakeTimers()
+    createOrder.mockResolvedValue(jsapiOrderFixture('resume-token-missing-bridge'))
+    ;(window as Window & { WeixinJSBridge?: { invoke: typeof bridgeInvoke } }).WeixinJSBridge = undefined
+
+    const wrapper = shallowMount(PaymentView, {
+      global: {
+        stubs: {
+          Teleport: true,
+          Transition: false,
+        },
+      },
+    })
+
+    await flushPromises()
+    await vi.advanceTimersByTimeAsync(4000)
+    await flushPromises()
+    await flushPromises()
+
+    expect(showError).toHaveBeenCalledWith(
+      'payment.errors.wechatJsapiUnavailable payment.errors.wechatOpenInWeChatHint',
+    )
+    expect(routerPush).not.toHaveBeenCalled()
+    expect(window.localStorage.getItem(PAYMENT_RECOVERY_STORAGE_KEY)).toBeNull()
+    expect(wrapper.html()).not.toContain('payment-status-panel-stub')
+  })
+
   it('clears a stale recovery snapshot before handling wechat resume callback params', async () => {
     createOrder.mockRejectedValueOnce(new Error('resume failed'))
     window.localStorage.setItem(PAYMENT_RECOVERY_STORAGE_KEY, JSON.stringify({