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## **Description**

Moves V2 ramp order state management from Redux (`FiatOrder`) into the
`RampsController`, eliminating the conversion layer where clean
`RampsOrder` API data was mangled into a legacy shape and immediately
cast back.

This PR will allow for future PRs such as a headless ramps experience
where callers can subscribe to order updates:
#26728

or implementing websocket connections for real-time order status
updates:
MetaMask/core#8075



Please reference loom videos below for a demo of this PR.

**What changed:**

- **Order creation** (Checkout + Transak native): `addOrder(rampsOrder)`
stores directly in controller state. No more `createInitialFiatOrder()`,
`rampsOrderToFiatOrder()`, or `dispatch(addFiatOrder())`. Transak
deposit orders merge `paymentDetails` from the `TransakDepositOrder`
onto the `RampsOrder` before storing, preserving inline bank transfer
details.

- **Order detail screen**: `OrderDetails` + `OrderContent` read
`RampsOrder` from controller state via `useRampsOrders` hook. No Redux,
no `processFiatOrder`, no `useInterval` polling. Pull-to-refresh calls
`refreshOrder()`. Controller polling keeps data fresh automatically.

- **Bank details screen**: `V2BankDetails` reads order lifecycle from
controller state and fetches deposit-specific data (payment details)
from `TransakService`. Cancel and confirm use `providerOrderId`
directly.

- **Orders list**: `OrdersList` merges legacy `FiatOrder[]` from Redux
with V2 `RampsOrder[]` from controller state via `DisplayOrder`
projection. Legacy orders route to the aggregator detail screen; V2
orders route to the new controller-native detail screen.

- **Side effects**: `ramps-controller-init.ts` subscribes to
`RampsController:orderStatusChanged` for notification and analytics
handlers, and starts controller order polling on init. Follows the same
pattern as `TransactionController:transactionConfirmed` handlers.

- **Messenger**: `RampsControllerInitMessenger` delegates the
`orderStatusChanged` event so init-level subscriptions work.

**What stays untouched:** Legacy `AGGREGATOR`, `DEPOSIT`, and older
orders remain in Redux. Their processors, detail screens, types, and
polling are unchanged.

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## **Changelog**

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CHANGELOG entry: null

## **Related issues**

Core PR that added orders MetaMask/core#8045

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**

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

### **After**


![Image](https://github.com/user-attachments/assets/bb026e42-5cbe-4542-8169-e1375cd31a39)

Loom video of the controller state being polled, created and updated for
Aggregator order (Moonpay)
https://www.loom.com/share/70658e66e55c444cadc02aad407c3da2

Loom video of the controller state being polled, created and updated for
Native order (Transak)
https://www.loom.com/share/2c6d5941cbfa48c4be7cc36000e40e89

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

## **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.



<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Medium Risk**
> Updates unified ramp checkout/order list navigation and switches V2
order creation/storage to controller state, which could impact order
visibility and detail routing for buy/deposit flows. Risk is mitigated
by updated unit tests, but regressions could affect transaction history
UX.
> 
> **Overview**
> **V2 ramp orders are now stored and read from `RampsController`
instead of being converted into legacy `FiatOrder` Redux state.**
`Checkout` uses `useRampsOrders` (`getOrderFromCallback`, `addOrder`)
and always `reset`s into `Routes.RAMP.RAMPS_ORDER_DETAILS` with
`showCloseButton`, even when order IDs are `null`.
> 
> **Orders list UI and navigation were reworked to merge legacy Redux
orders with controller V2 orders.** `OrdersList` now projects both into
a unified `DisplayOrder` list (`mergeDisplayOrders`), renders new list
rows, and routes presses by source/provider (legacy aggregator ->
`OrderDetails`, V2 -> `RampsOrderDetails`, deposit -> new
`DepositOrderDetails`, created deposit -> deposit flow).
> 
> Adds `Routes.DEPOSIT.ORDER_DETAILS` to the main navigator and updates
provider selection to consider completed controller orders when
computing previously-used providers. Tests/snapshots were updated
accordingly, and V2 toast wiring now passes `status` (typed as
`RampsOrderStatus`) instead of legacy `state`.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
f7c7f73. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

---------

Co-authored-by: Cursor Agent <cursoragent@cursor.com>