…lay to RC and production builds. (#29390)

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## **Description**
Adds automated build environment display to RC and production builds.
Captures actual environment values used during builds
(METAMASK_ENVIRONMENT, METAMASK_BUILD_TYPE, API URLs, etc.) and displays
them:
- RC builds: In PR comment alongside build links
- Prod builds: Extracted via new workflow (Slack notification in
follow-up PR).
 
**Changes:**
- scripts/apply-build-config.js: Add --write-build-env flag to generate
build-env.json with actual env values
- build.yml: Generate and upload build-env.json as artifact during
builds (used by both RC and
prod)
- build-rc-auto.yml: Download build-env artifacts in
post-rc-build-comment job
- scripts/build-announce/: Add env section to RC build PR comments
- prod-build-env-notify.yml: New workflow triggered on prod build
completion, extracts env values (Slack posting in follow-up PR)
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also include relevant motivation and context. Have in mind the following
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2. What is the improvement/solution?
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## **Changelog**

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`CHANGELOG entry: Added a new tab for users to see their NFTs`
`CHANGELOG entry: Fixed a bug that was causing some NFTs to flicker`

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CHANGELOG entry: null

## **Related issues**

Fixes:
https://consensyssoftware.atlassian.net/browse/MMQA-1108
## **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**

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

## **Pre-merge author checklist**

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- [ ] 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).
- [ ] I've completed the PR template to the best of my ability
- [ ] I've included tests if applicable
- [ ] I've documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [ ] 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)

- [ ] 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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- [ ] 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]
> **Medium Risk**
> Changes CI build workflows and the RC PR-comment pipeline to generate,
upload, download, and parse a new `build-env.json` artifact;
misconfiguration could break build jobs or PR comment posting. Risk is
limited to CI/reporting paths and is largely non-blocking
(`continue-on-error`/`|| true`) but still touches release build
automation.
> 
> **Overview**
> Adds generation of a `build-env.json` file during CI builds (via
`scripts/apply-build-config.js --write-build-env`) and uploads it as a
build artifact for each platform.
> 
> Updates RC automation to download these artifacts and extends
`scripts/build-announce` to parse them and include a **Build
Environment** section (env/build type, remote FF mapping, key API
URLs/flags) in the RC PR comment, with a fallback “not available”
section on extraction failure.
> 
> Introduces a new `Prod Build Env Notify` workflow that triggers on
successful production workflow runs, downloads the `build-env` artifact,
extracts key values with `jq`, and currently prints a placeholder for a
future Slack notification; also ignores local `build-env.json` via
`.gitignore`.
> 
> <sup>Reviewed by [Cursor Bugbot](https://cursor.com/bugbot) for commit
0f0c4b5. Bugbot is set up for automated
code reviews on this repo. Configure
[here](https://www.cursor.com/dashboard/bugbot).</sup>
<!-- /CURSOR_SUMMARY -->