feat: Enable BSC for smart transactions (#29747)

## **Description**
Enables BSC for smart transactions and reduces status check time to 1s.

We can turn off BSC support for smart transactions remotely if needed.

[![Open in GitHub
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## **Related issues**

Fixes:

## **Manual testing steps**

1. Make sure smart transactions are enabled in Advanced Settings
2. Be on the BNB Chain
3. Submit a tx. It will be submitted as a smart transaction

Happy paths tested for Swaps, Send and dapp transactions, but this will
require extensive testing before it goes to production.

## **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
Extension Coding
Standards](https://github.com/MetaMask/metamask-extension/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-extension/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.

Author: dan437

shared/constants/smartTransactions.test.ts

@@ -21,13 +21,14 @@ describe('smartTransactions', () => {
       expect(allowedChainIds).toStrictEqual([
         CHAIN_IDS.MAINNET,
         CHAIN_IDS.SEPOLIA,
+        CHAIN_IDS.BSC,
       ]);
     });
 
     it('should return the correct chain IDs for production environment', () => {
       mockIsProduction.mockReturnValue(true);
       const allowedChainIds = getAllowedSmartTransactionsChainIds();
-      expect(allowedChainIds).toStrictEqual([CHAIN_IDS.MAINNET]);
+      expect(allowedChainIds).toStrictEqual([CHAIN_IDS.MAINNET, CHAIN_IDS.BSC]);
     });
   });
 });

shared/constants/smartTransactions.ts

@@ -11,10 +11,12 @@ export const FALLBACK_SMART_TRANSACTIONS_MAX_FEE_MULTIPLIER: number = 2;
 const ALLOWED_SMART_TRANSACTIONS_CHAIN_IDS_DEVELOPMENT: string[] = [
   CHAIN_IDS.MAINNET,
   CHAIN_IDS.SEPOLIA,
+  CHAIN_IDS.BSC,
 ];
 
 const ALLOWED_SMART_TRANSACTIONS_CHAIN_IDS_PRODUCTION: string[] = [
   CHAIN_IDS.MAINNET,
+  CHAIN_IDS.BSC,
 ];
 
 export const getAllowedSmartTransactionsChainIds = (): string[] => {