fix: MUSD-772 fix earn deposits redirecting to activity view with no way to leave (#29763)

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## **Description**
Fixes a regression introduced in
#29454 where Earn
redirects to the activity view for successful pooled-staking or lending
deposits would leave users stranded without a way to exit.

This comes as part of a larger change to replace activity with Money in
the main navbar.

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CHANGELOG entry: Fixes a regression where Earn redirects to the activity
view for successful pooled-staking or lending deposits would leave users
stranded without a way to exit.

## **Related issues**

Fixes: [MUSD-772: Fix deposit redirects for Earn flows leaving users
stranded on Activity
page](https://consensyssoftware.atlassian.net/browse/MUSD-772)

## **Manual testing steps**

```gherkin
Feature: Activity screen navigation when Money Home is enabled

  Scenario: user accesses activity list from Money Home
    Given the Money Home feature flag is enabled
    And user is on the pooled-staking or lending deposit confirmation screen

    When confirms their transaction
    Then user is redirected to the activty with
    And a back button is displayed in the Activity screen header
    And user can navigate back to Wallet Home without being stranded
```

## **Screenshots/Recordings**

<!-- If applicable, add screenshots and/or recordings to visualize the
before and after of your change. -->

### **Before**

<!-- [screenshots/recordings] -->


https://github.com/user-attachments/assets/85bb5c72-978e-4e63-86b4-e35bb35e83da

### **After**

<!-- [screenshots/recordings] -->


https://github.com/user-attachments/assets/5752d2aa-7f8b-4b32-bec8-b58b5eb2351b

## **Pre-merge author checklist**

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- [x] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask Mobile
Coding
Standards](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [x] I've completed the PR template to the best of my ability
- [x] I've included tests if applicable
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if applicable
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guidelines](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.

#### Performance checks (if applicable)

- [ ] I've tested on Android
  - Ideally on a mid-range device; emulator is acceptable
- [ ] I've tested with a power user scenario
- Use these [power-user
SRPs](https://consensyssoftware.atlassian.net/wiki/spaces/TL1/pages/edit-v2/401401446401?draftShareId=9d77e1e1-4bdc-4be1-9ebb-ccd916988d93)
to import wallets with many accounts and tokens
- [ ] I've instrumented key operations with Sentry traces for production
performance metrics
- See [`trace()`](/app/util/trace.ts) for usage and
[`addToken`](/app/components/Views/AddAsset/components/AddCustomToken/AddCustomToken.tsx#L274)
for an example

For performance guidelines and tooling, see the [Performance
Guide](https://consensyssoftware.atlassian.net/wiki/spaces/TL1/pages/400085549067/Performance+Guide+for+Engineers).

## **Pre-merge reviewer checklist**

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- [ ] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [ ] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Medium Risk**
> Changes back-navigation behavior (including Android hardware back
handling) for `ActivityView` when the Money Home feature flag is
enabled, which could affect user navigation flows if routing assumptions
are wrong. Scope is limited and covered by new unit tests around back
button and hardware back handling.
> 
> **Overview**
> Fixes a regression where users redirected into `ActivityView` (e.g.,
after successful Earn deposits) could get stuck without a reliable way
to exit when the Money Home experience is enabled.
> 
> When `selectMoneyHomeScreenEnabledFlag` is on, `ActivityView` now
always shows a back button and routes both header back and Android
`hardwareBackPress` to `Routes.HOME_TABS` (instead of returning to the
prior stack/confirmation screen). The wallet’s Activity entrypoint no
longer passes `showBackButton` params, and `Routes` adds a new
`HOME_TABS` route constant.
> 
> Adds/updates `ActivityView` tests to cover Money-flag behavior for
header back, hardware back interception, and header variant selection.
> 
> <sup>Reviewed by [Cursor Bugbot](https://cursor.com/bugbot) for commit
e5a0c60. Bugbot is set up for automated
code reviews on this repo. Configure
[here](https://www.cursor.com/dashboard/bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: Matt561

app/components/Views/ActivityView/index.js

@@ -1,6 +1,6 @@
 import { useFocusEffect, useNavigation } from '@react-navigation/native';
-import React, { useCallback, useMemo, useState } from 'react';
-import { StyleSheet, View } from 'react-native';
+import React, { useCallback, useEffect, useMemo, useState } from 'react';
+import { BackHandler, StyleSheet, View } from 'react-native';
 import { SafeAreaView } from 'react-native-safe-area-context';
 import { useSelector } from 'react-redux';
 import { WalletViewSelectorsIDs } from '../Wallet/WalletView.testIds';
@@ -23,11 +23,13 @@ import { KnownCaipNamespace } from '@metamask/utils';
 import { selectIsEvmNetworkSelected } from '../../../selectors/multichainNetworkController';
 import { selectChainId } from '../../../selectors/networkController';
 import { selectNetworkName } from '../../../selectors/networkInfos';
+import Routes from '../../../constants/navigation/Routes';
 import { useParams } from '../../../util/navigation/navUtils';
 import { getNetworkImageSource } from '../../../util/networks';
 import { useTheme } from '../../../util/theme';
 import { TabsList } from '../../../component-library/components-temp/Tabs';
 import { createNetworkManagerNavDetails } from '../../UI/NetworkManager';
+import { selectMoneyHomeScreenEnabledFlag } from '../../UI/Money/selectors/featureFlags';
 import { selectPerpsEnabledFlag } from '../../UI/Perps';
 import { selectPredictEnabledFlag } from '../../UI/Predict/selectors/featureFlags';
 import PredictTransactionsView from '../../UI/Predict/views/PredictTransactionsView/PredictTransactionsView';
@@ -106,6 +108,10 @@ const ActivityView = () => {
 
   const currentNetworkName = getNetworkInfo(0)?.networkName;
 
+  const isMoneyHomeScreenEnabled = useSelector(
+    selectMoneyHomeScreenEnabledFlag,
+  );
+
   const params = useParams();
   const perpsEnabledFlag = useSelector(selectPerpsEnabledFlag);
   const isPerpsEnabled = useMemo(
@@ -123,13 +129,34 @@ const ActivityView = () => {
     navigation.navigate(...createNetworkManagerNavDetails({}));
   };
 
+  // Prevent back button returning to confirmation screen in case that users are redirected after a successful transaction.
+  const handleNavigateHome = useCallback(() => {
+    navigation.navigate(Routes.HOME_TABS);
+  }, [navigation]);
+
   const handleBackPress = useCallback(() => {
-    if (navigation.canGoBack()) {
+    if (isMoneyHomeScreenEnabled) {
+      handleNavigateHome();
+    } else if (navigation.canGoBack()) {
       navigation.goBack();
     }
-  }, [navigation]);
+  }, [isMoneyHomeScreenEnabled, navigation, handleNavigateHome]);
+
+  useEffect(() => {
+    if (!isMoneyHomeScreenEnabled) return;
+
+    const subscription = BackHandler.addEventListener(
+      'hardwareBackPress',
+      () => {
+        handleNavigateHome();
+        return true;
+      },
+    );
+
+    return () => subscription.remove();
+  }, [navigation, isMoneyHomeScreenEnabled, handleNavigateHome]);
 
-  const showBackButton = params.showBackButton || false;
+  const showBackButton = params.showBackButton || isMoneyHomeScreenEnabled;
 
   // Calculate dynamic tab indices based on which tabs are enabled
   // Tab order: Transactions (0), Orders (1), Perps (conditional), Predict (conditional)

app/components/Views/ActivityView/index.test.tsx

@@ -1,14 +1,21 @@
 import React from 'react';
 import ActivityView from '.';
+import { BackHandler } from 'react-native';
 import { backgroundState } from '../../../util/test/initial-root-state';
 import renderWithProvider from '../../../util/test/renderWithProvider';
 import { createStackNavigator } from '@react-navigation/stack';
-import { fireEvent } from '@testing-library/react-native';
+import { cleanup, fireEvent } from '@testing-library/react-native';
 // eslint-disable-next-line import-x/no-namespace
 import * as networkManagerUtils from '../../UI/NetworkManager';
 import { useCurrentNetworkInfo } from '../../hooks/useCurrentNetworkInfo';
 import { ActivitiesViewSelectorsIDs } from './ActivitiesView.testIds';
 import { WalletViewSelectorsIDs } from '../Wallet/WalletView.testIds';
+import Routes from '../../../constants/navigation/Routes';
+
+let mockMoneyHomeScreenEnabled = false;
+jest.mock('../../UI/Money/selectors/featureFlags', () => ({
+  selectMoneyHomeScreenEnabledFlag: jest.fn(() => mockMoneyHomeScreenEnabled),
+}));
 
 // Mock the Perps feature flag selector - will be controlled per test
 let mockPerpsEnabled = false;
@@ -236,6 +243,8 @@ describe('ActivityView', () => {
   const mockUseCurrentNetworkInfo =
     useCurrentNetworkInfo as jest.MockedFunction<typeof useCurrentNetworkInfo>;
 
+  let backHandlerSpy: jest.SpyInstance;
+
   const defaultNetworkInfo = {
     enabledNetworks: [
       { chainId: '0x1', enabled: true },
@@ -266,15 +275,26 @@ describe('ActivityView', () => {
 
   beforeEach(() => {
     jest.clearAllMocks();
+    backHandlerSpy = jest
+      .spyOn(BackHandler, 'addEventListener')
+      .mockReturnValue({ remove: jest.fn() } as unknown as ReturnType<
+        typeof BackHandler.addEventListener
+      >);
     mockUseCurrentNetworkInfo.mockReturnValue(defaultNetworkInfo);
     mockIsEvmSelected = true;
+    mockMoneyHomeScreenEnabled = false;
     mockPerpsEnabled = false;
     mockPredictEnabled = false;
     mockAreAllEvmPopularNetworksEnabled = false;
     clearRenderedTabs();
     mockRoute.params = {};
   });
 
+  afterEach(() => {
+    cleanup();
+    backHandlerSpy.mockRestore();
+  });
+
   describe('Network Manager Integration', () => {
     beforeEach(() => {
       jest.clearAllMocks();
@@ -403,6 +423,80 @@ describe('ActivityView', () => {
 
       expect(mockNavigation.goBack).not.toHaveBeenCalled();
     });
+
+    it('displays back button when Money home screen flag is enabled without showBackButton param', () => {
+      mockMoneyHomeScreenEnabled = true;
+      mockRoute.params = {};
+
+      const { getByTestId } = renderComponent(mockInitialState);
+
+      expect(getByTestId('activity-view-back-button')).toBeOnTheScreen();
+    });
+
+    it('calls navigation.navigate with HOME_TABS on back button press when Money flag is enabled', () => {
+      mockMoneyHomeScreenEnabled = true;
+      mockRoute.params = {};
+      const { getByTestId } = renderComponent(mockInitialState);
+
+      fireEvent.press(getByTestId('activity-view-back-button'));
+
+      expect(mockNavigation.navigate).toHaveBeenCalledWith(Routes.HOME_TABS);
+      expect(mockNavigation.goBack).not.toHaveBeenCalled();
+    });
+
+    it('calls navigation.navigate with HOME_TABS and not goBack when both flag and showBackButton param are true', () => {
+      mockMoneyHomeScreenEnabled = true;
+      mockRoute.params = { showBackButton: true };
+      const { getByTestId } = renderComponent(mockInitialState);
+
+      fireEvent.press(getByTestId('activity-view-back-button'));
+
+      expect(mockNavigation.navigate).toHaveBeenCalledWith(Routes.HOME_TABS);
+      expect(mockNavigation.goBack).not.toHaveBeenCalled();
+    });
+
+    it('registers hardwareBackPress handler when Money flag is enabled', () => {
+      mockMoneyHomeScreenEnabled = true;
+      mockRoute.params = {};
+
+      renderComponent(mockInitialState);
+
+      expect(BackHandler.addEventListener).toHaveBeenCalledWith(
+        'hardwareBackPress',
+        expect.any(Function),
+      );
+    });
+
+    it('navigates to HOME_TABS when hardwareBackPress fires with Money flag enabled', () => {
+      mockMoneyHomeScreenEnabled = true;
+      mockRoute.params = {};
+      renderComponent(mockInitialState);
+      const [[, handler]] = (BackHandler.addEventListener as jest.Mock).mock
+        .calls;
+
+      const result = handler();
+
+      expect(mockNavigation.navigate).toHaveBeenCalledWith(Routes.HOME_TABS);
+      expect(result).toBe(true);
+    });
+
+    it('does not navigate to HOME_TABS on hardwareBackPress when Money flag is disabled', () => {
+      mockMoneyHomeScreenEnabled = false;
+      mockRoute.params = {};
+
+      renderComponent(mockInitialState);
+
+      const hardwareBackPressCalls = (
+        BackHandler.addEventListener as jest.Mock
+      ).mock.calls.filter(([event]: [string]) => event === 'hardwareBackPress');
+      hardwareBackPressCalls.forEach(([, handler]: [string, () => boolean]) =>
+        handler(),
+      );
+
+      expect(mockNavigation.navigate).not.toHaveBeenCalledWith(
+        Routes.HOME_TABS,
+      );
+    });
   });
 
   describe('header and SafeAreaView', () => {
@@ -463,6 +557,18 @@ describe('ActivityView', () => {
         queryByTestId(ActivitiesViewSelectorsIDs.HEADER_COMPACT_STANDARD),
       ).toBeNull();
     });
+
+    it('renders HeaderCompactStandard when Money home screen flag is enabled', () => {
+      mockMoneyHomeScreenEnabled = true;
+      mockRoute.params = {};
+
+      const { getByTestId, queryByTestId } = renderComponent(mockInitialState);
+
+      expect(
+        getByTestId(ActivitiesViewSelectorsIDs.HEADER_COMPACT_STANDARD),
+      ).toBeOnTheScreen();
+      expect(queryByTestId(ActivitiesViewSelectorsIDs.HEADER_ROOT)).toBeNull();
+    });
   });
 
   describe('Perps tab', () => {

app/components/Views/Wallet/index.tsx

@@ -1061,10 +1061,7 @@ const Wallet = ({
         MetaMetricsEvents.ACTIVITY_CLICKED,
       ).build(),
     );
-    navigation.navigate(Routes.TRANSACTIONS_VIEW, {
-      screen: Routes.TRANSACTIONS_VIEW,
-      params: { showBackButton: true },
-    });
+    navigation.navigate(Routes.TRANSACTIONS_VIEW);
   }, [navigation, trackEvent]);
 
   const getTokenAddedAnalyticsParams = useCallback(

app/constants/navigation/Routes.ts

@@ -1,4 +1,5 @@
 const Routes = {
+  HOME_TABS: 'Home',
   WALLET_VIEW: 'WalletView',
   BROWSER_TAB_HOME: 'BrowserTabHome',
   BROWSER_VIEW: 'BrowserView',