chore(runway): cherry-pick fix: point DIGEST_API_URL to production endpoint (#28088)

## **Description**

<!-- 1. What is the reason for the change? The fallback URL for
`DIGEST_API_URL` was pointing at the development endpoint. -->
<!-- 2. What is the improvement/solution? Switch the hardcoded fallback
to the production endpoint so that builds without an explicit env var
hit production. -->

Switches the hardcoded fallback value for `DIGEST_API_URL` in
`AppConstants.ts` from the dev endpoint
(`digest.dev-api.cx.metamask.io`) to the production endpoint
(`digest.api.cx.metamask.io`).

Also moves the `@metamask/sdk-communication-layer` import to the top of
the file to follow alphabetical import ordering.

## **Changelog**

CHANGELOG entry: null

## **Related issues**

Fixes:

## **Manual testing steps**

N/A

## **Screenshots/Recordings**

### **Before**

N/A

### **After**

N/A

## **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
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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).
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in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.

<!-- Generated with the help of the pr-description AI skill -->

Made with [Cursor](https://cursor.com)

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Low Risk**
> Low risk: only changes a constant fallback URL and import ordering.
Main impact is that builds without `DIGEST_API_URL` will now call the
production digest service instead of the dev endpoint.
> 
> **Overview**
> Updates `AppConstants.DIGEST_API_URL` to default to the production
`https://digest.api.cx.metamask.io/api/v1` endpoint when the
`DIGEST_API_URL` env var is not set.
> 
> Also reorders the `DEFAULT_SERVER_URL` import to match expected import
ordering.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
9d584a4. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: xavier-brochard

app/core/AppConstants.ts

@@ -1,6 +1,6 @@
+import { DEFAULT_SERVER_URL } from '@metamask/sdk-communication-layer';
 import { CoreTypes } from '@walletconnect/types';
 import Device from '../util/device';
-import { DEFAULT_SERVER_URL } from '@metamask/sdk-communication-layer';
 
 const DEVELOPMENT = 'development';
 
@@ -214,8 +214,7 @@ export default {
     process.env.DECODING_API_URL ||
     'https://signature-insights.api.cx.metamask.io/v1',
   DIGEST_API_URL:
-    process.env.DIGEST_API_URL ||
-    'https://digest.dev-api.cx.metamask.io/api/v1',
+    process.env.DIGEST_API_URL || 'https://digest.api.cx.metamask.io/api/v1',
   // Rewards/Baanx: GH Actions use builds.yml (env set per build). Fallback mapping for local when env not set.
   REWARDS_API_URL: {
     DEV: 'https://rewards.dev-api.cx.metamask.io',