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## **Description**

This PR consolidates navigation styles across the codebase by replacing
inline `navigationOptions` style definitions with the shared
`getNavigationOptionsTitle` utility function.

**Reason for change:**
- Preparing the codebase for the upgrade to React Navigation v6
- Navigation header styles were defined inconsistently across components
using the legacy `navigationOptions` pattern
- Centralizing navigation options will make the migration to React
Navigation v6's new API smoother and reduce the scope of changes
required during the upgrade

**Solution:**
- Replaced inline style definitions with the centralized
`getNavigationOptionsTitle` function from `app/components/UI/Navbar`
- This ensures consistent navigation header styling across the app and
simplifies the upcoming React Navigation v6 migration

## **Changelog**

CHANGELOG entry: null

## **Related issues**

Fixes: #23765 Part of
React Navigation v6 upgrade preparation (split from original PR for
easier code review by team)

## **Manual testing steps**

Feature: Navigation header consistency

  Scenario: User navigates to screens affected by this PR
    Given the app is running

    When user navigates to any screen modified in this PR
Then the navigation header should display correctly with proper title
styling
    And the back button should function as expected
## **Screenshots/Recordings**

<!-- No visual changes expected - this is a code refactoring PR -->

### **Before**

N/A - No visual changes

### **After**

N/A - No visual changes

## **Pre-merge author checklist**

- [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
- [x] I've documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [x] I've applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.

## **Pre-merge reviewer checklist**

- [ ] 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.](#25877)

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Medium Risk**
> Touches navigation behavior in confirmation and account-switch flows,
so small route/stack differences could change where users land or how
modals close. Changes are localized and covered by updated tests.
> 
> **Overview**
> Consolidates confirmations-related navigation by replacing the nested
`navigation.navigate(Routes.WALLET.HOME, { ...Routes.WALLET_VIEW... })`
pattern with a direct `navigation.navigate(Routes.WALLET_VIEW)`.
> 
> This updates the switch-account-type modal’s close behavior
(`AccountNetworkRow`), the post-confirm flow for
`TransactionType.musdConversion` (`useTransactionConfirm`), and the
“reject then go home” path (`useConfirmActions`), with associated test
expectation updates.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
0d8b7de. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->