## **Description**

Introduce Hardened JavaScript now on both iOS (RN JSC) and Android
(Hermes)
via Metro (@lavamoat/react-native-lockdown beta) instead of RN patch
and remove [old iOS
UI](https://github.com/user-attachments/assets/b53be562-bc36-4ff2-a177-ef5c24c44de4)
from: Settings > Experimental > Security

TODO
- [x] Remove stale root SES shim (now via
@lavamoat/react-native-lockdown)
- [x] Remove stale RN iOS patch (now via
@lavamoat/react-native-lockdown)
- [x] Add temp @lavamoat/react-native-lockdown tgz
- [x] Add temp SES patch endojs/endo#2855
- [x] Replace both with official @lavamoat/react-native-lockdown
  - [x] once LavaMoat/LavaMoat#1716 merged
  - [x] released LavaMoat/LavaMoat#1643
- [x] Remove experimental feature toggle UI
  - Ref: #8373
    - preserve react-native-mmkv (we still use it)
    - update UI component snapshot
    - remove stale EN txt (and others?)
- [x] <s>Fix smoke/regression e2e test timeouts</s> passing
- [x] check failing regression e2e tests
  - same ones also failing on `main`
- [x] cursor[bot] feedback

## **Related issues**

Fixes:

## **Manual testing steps**

## **Screenshots/Recordings**

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

### **Before**

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### **After**

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## **Pre-merge author checklist**

- [ ] 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.

## **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.

---------

Co-authored-by: sethkfman <10342624+sethkfman@users.noreply.github.com>