refactor(aggregator): migrate aggregator routes to native stack (MetaMask#30611)

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## **Description**
Migrates the legacy aggregator routes (`Aggregator/routes/index.tsx`)
from `@react-navigation/stack` (JS stack) to
`@react-navigation/native-stack`, aligning with the rest of the Ramp
routing tree (Unified V2 `Ramp/routes.tsx` already uses native stack).

Native stack uses platform-native navigation primitives
(`UINavigationController` on iOS, `FragmentTransaction` on Android),
which yields better performance and a more native feel — especially
noticeable on the modal/overlay transitions used by `Quotes` and
`Checkout`.

The migration is purely a wiring/config change. No screen behaviour,
route names, or component imports change. Translations applied:
- Navigator: `createStackNavigator` → `createNativeStackNavigator`
- Per-screen overlay options: replaced inline `headerShown / cardStyle /
animationEnabled / detachPreviousScreen` blocks for `Quotes` and
`Checkout` with the shared `clearNativeStackNavigatorOptions` +
`transparentModalScreenOptions` presets from
`app/constants/navigation/clearStackNavigatorOptions.ts`.
- Property renames: `cardStyle` → `contentStyle`, `animationEnabled:
false` → `animation: 'none'`.
- The `detachPreviousScreen: false` workaround used to keep the
underlying screen mounted under transparent modals is no longer needed —
native stack keeps the presenting screen mounted automatically when
`presentation: 'transparentModal'` is used.
- Removed the now-unused `colors` import (it was only used to set
`cardStyle.backgroundColor: colors.transparent`).
 
Test mock in `routes/index.test.tsx` updated to mock
`@react-navigation/native-stack` (`createNativeStackNavigator`) instead
of `@react-navigation/stack`.


## **Changelog**

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CHANGELOG entry:null

## **Related issues**

Fixes:

## **Manual testing steps**

```gherkin
Feature: my feature name

  Scenario: user [verb for user action]
    Given [describe expected initial app state]

    When user [verb for user action]
    Then [describe expected outcome]
```

## **Screenshots/Recordings**

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

### **Before**
<img width="364" height="752" alt="Aggregator Before"
src="https://github.com/user-attachments/assets/423ec7f4-66b2-48dd-bfc2-ab2769eaf260"
/>

### **After**
<img width="364" height="752" alt="Aggregator After"
src="https://github.com/user-attachments/assets/e545af4e-9b7d-4907-a343-6475c44ba0be"
/>

Android

https://github.com/user-attachments/assets/9df9f89d-3c4e-4e49-ac32-ba3896d0384f

## **Pre-merge author checklist**

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"Ready for review". A checked box means you deliberately considered that
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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
- [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.

#### Performance checks (if applicable)

- [x] 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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checklist: an
unchecked box is ambiguous, a checked box means the reviewer consciously
assessed that responsibility. See `docs/readme/ready-for-review.md`.
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- [x] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [x] 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]
> **Low Risk**
> Navigation-only wiring in Ramp Aggregator routes; no business logic,
auth, or data handling changes.
> 
> **Overview**
> **Aggregator Ramp routing** now uses `@react-navigation/native-stack`
instead of the JS stack, matching the newer Ramp navigation setup while
leaving screens and route names unchanged.
> 
> **Quotes**, **Checkout**, and the nested **modals** stack pick up
shared `clearNativeStackNavigatorOptions` and
`transparentModalScreenOptions` instead of inline `cardStyle` /
`animationEnabled` / `detachPreviousScreen` workarounds;
`BUILD_QUOTE_HAS_STARTED` uses `animation: 'none'`. The route test mock
was updated to `createNativeStackNavigator`.
> 
> <sup>Reviewed by [Cursor Bugbot](https://cursor.com/bugbot) for commit
371f725. Bugbot is set up for automated
code reviews on this repo. Configure
[here](https://www.cursor.com/dashboard/bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: weitingsun

app/components/UI/Ramp/Aggregator/routes/index.test.tsx

@@ -8,8 +8,8 @@ import { RampType } from '../types';
 import Routes from '../../../../../constants/navigation/Routes';
 import { backgroundState } from '../../../../../util/test/initial-root-state';
 
-jest.mock('@react-navigation/stack', () => ({
-  createStackNavigator: jest.fn().mockReturnValue({
+jest.mock('@react-navigation/native-stack', () => ({
+  createNativeStackNavigator: jest.fn().mockReturnValue({
     Navigator: ({ children }: { children: React.ReactNode }) => children,
     Screen: ({
       name,

app/components/UI/Ramp/Aggregator/routes/index.tsx

@@ -1,5 +1,5 @@
 import React from 'react';
-import { createStackNavigator } from '@react-navigation/stack';
+import { createNativeStackNavigator } from '@react-navigation/native-stack';
 import Quotes from '../Views/Quotes';
 import CheckoutWebView from '../Views/Checkout';
 import BuildQuote from '../Views/BuildQuote';
@@ -10,52 +10,51 @@ import FiatSelectorModal from '../components/FiatSelectorModal';
 import { RampType } from '../types';
 import { RampSDKProvider } from '../sdk';
 import Routes from '../../../../../constants/navigation/Routes';
-import { colors } from '../../../../../styles/common';
 import IncompatibleAccountTokenModal from '../components/IncompatibleAccountTokenModal';
 import RegionSelectorModal from '../components/RegionSelectorModal';
 import UnsupportedRegionModal from '../components/UnsupportedRegionModal';
 import SettingsModal from '../Views/Modals/Settings';
-import { clearStackNavigatorOptions } from '../../../../../constants/navigation/clearStackNavigatorOptions';
+import {
+  clearNativeStackNavigatorOptions,
+  transparentModalScreenOptions,
+} from '../../../../../constants/navigation/clearStackNavigatorOptions';
 
-const Stack = createStackNavigator();
-const ModalsStack = createStackNavigator();
+const Stack = createNativeStackNavigator();
+const ModalsStack = createNativeStackNavigator();
+
+const overlayScreenOptions = {
+  ...clearNativeStackNavigatorOptions,
+  ...transparentModalScreenOptions,
+  gestureEnabled: false,
+};
 
 const MainRoutes = () => (
   <Stack.Navigator initialRouteName={Routes.RAMP.BUILD_QUOTE}>
     <Stack.Screen name={Routes.RAMP.BUILD_QUOTE} component={BuildQuote} />
     <Stack.Screen
       name={Routes.RAMP.BUILD_QUOTE_HAS_STARTED}
       component={BuildQuote}
-      options={{ animationEnabled: false }}
+      options={{ animation: 'none' }}
     />
     <Stack.Screen
       name={Routes.RAMP.QUOTES}
       component={Quotes}
-      options={{
-        headerShown: false,
-        cardStyle: { backgroundColor: colors.transparent },
-        animationEnabled: false,
-        gestureEnabled: false,
-        detachPreviousScreen: false,
-      }}
+      options={overlayScreenOptions}
     />
     <Stack.Screen
       name={Routes.RAMP.CHECKOUT}
       component={CheckoutWebView}
-      options={{
-        headerShown: false,
-        cardStyle: { backgroundColor: colors.transparent },
-        animationEnabled: false,
-        gestureEnabled: false,
-        detachPreviousScreen: false,
-      }}
+      options={overlayScreenOptions}
     />
   </Stack.Navigator>
 );
 
 const RampModalsRoutes = () => (
   <ModalsStack.Navigator
-    screenOptions={{ ...clearStackNavigatorOptions, presentation: 'modal' }}
+    screenOptions={{
+      ...clearNativeStackNavigatorOptions,
+      presentation: 'modal',
+    }}
   >
     <ModalsStack.Screen
       name={Routes.RAMP.MODALS.TOKEN_SELECTOR}
@@ -100,8 +99,8 @@ const RampRoutes = ({ rampType }: { rampType: RampType }) => (
         name={Routes.RAMP.MODALS.ID}
         component={RampModalsRoutes}
         options={{
-          ...clearStackNavigatorOptions,
-          detachPreviousScreen: false,
+          ...clearNativeStackNavigatorOptions,
+          ...transparentModalScreenOptions,
         }}
       />
     </Stack.Navigator>