fix(checkout): stop replacing entire window object in connect tests

The window spy mock replaced window with a minimal object missing URL,
document, and other globals. Leaked async operations (getAllBalances ->
RemoteConfigFetcher) that use XMLHttpRequest would crash in CI because
jsdom couldn't find URL on the mocked window. Now we only mock
window.ethereum directly, preserving the real window globals.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: ImmutableJeffrey

packages/checkout/sdk/src/connect/connect.test.ts

@@ -8,28 +8,26 @@ import { WrappedBrowserProvider, WalletAction, WalletProviderName } from '../typ
 import { CheckoutErrorType } from '../errors';
 import { createProvider } from '../provider';
 
-let windowSpy: any;
-
 describe('connect', () => {
   const providerRequestMock: jest.Mock = jest.fn();
+  let originalEthereum: any;
+
   beforeEach(() => {
-    windowSpy = jest.spyOn(window, 'window', 'get');
-
-    windowSpy.mockImplementation(() => ({
-      ethereum: {
-        request: providerRequestMock,
-        isMetaMask: true,
-        on: jest.fn(),
-        removeListener: jest.fn(),
-      },
-      dispatchEvent: jest.fn(),
-      addEventListener: jest.fn(),
-      removeEventListener: jest.fn(),
-    }));
+    originalEthereum = (window as any).ethereum;
+    (window as any).ethereum = {
+      request: providerRequestMock,
+      isMetaMask: true,
+      on: jest.fn(),
+      removeListener: jest.fn(),
+    };
   });
 
   afterEach(() => {
-    windowSpy.mockRestore();
+    if (originalEthereum === undefined) {
+      delete (window as any).ethereum;
+    } else {
+      (window as any).ethereum = originalEthereum;
+    }
   });
 
   describe('checkIsWalletConnected', () => {
@@ -129,16 +127,11 @@ describe('connect', () => {
     });
 
     it('should throw an error if the user rejects the connection request', async () => {
-      windowSpy.mockImplementation(() => ({
-        ethereum: {
-          request: jest
-            .fn()
-            .mockRejectedValue(new Error('User rejected request')),
-        },
-        removeEventListener: jest.fn(),
-        addEventListener: jest.fn(),
-        dispatchEvent: jest.fn(),
-      }));
+      (window as any).ethereum = {
+        request: jest
+          .fn()
+          .mockRejectedValue(new Error('User rejected request')),
+      };
 
       const { provider } = await createProvider(WalletProviderName.METAMASK);
 
@@ -182,14 +175,11 @@ describe('connect', () => {
     });
 
     it('should throw an error if the user rejects the permission request', async () => {
-      windowSpy.mockImplementation(() => ({
-        ethereum: {
-          request: jest
-            .fn()
-            .mockRejectedValue(new Error('User rejected request')),
-        },
-        removeEventListener: () => {},
-      }));
+      (window as any).ethereum = {
+        request: jest
+          .fn()
+          .mockRejectedValue(new Error('User rejected request')),
+      };
 
       const { provider } = await createProvider(WalletProviderName.METAMASK);