feat: add BSC to supported chains

[httpJunkie]

Description

What is the reason for the change?

Smart Transactions are not currently supported on BNB Smart Chain. As part of our effort to expand Smart Transactions functionality to more networks, BSC needs to be added to the list of supported chains.

What is the improvement/solution?

This PR adds BSC to the list of supported chains for Smart Transactions in the mobile app by:

• Adding NETWORKS_CHAIN_ID.BSC to ALLOWED_SMART_TRANSACTIONS_CHAIN_IDS_DEVELOPMENT for testing in development environments
• Temporarily keeping BSC commented out in production with a TODO comment for when backend support is ready
• Updating tests to reflect these changes

These changes allow the app to recognize Base as a valid network for Smart Transactions in development environments, while ensuring we maintain a safe rollout approach for production.

Related issues

Fixes:
TXL-704

Manual testing steps

Since Base isn't fully supported in production yet, this PR implements a phased approach:

1. Enable BSC for Smart Transactions in development environments
2. Keep it commented out in production until backend support is verified
3. Update UI text to be network-agnostic

Manual testing included:

• Verified existing Smart Transactions still work on Ethereum Mainnet
• Checked network switching between supported networks
• Confirmed Smart Transactions settings UI correctly displays the updated description
• Verified Smart Transactions can be toggled on/off in settings

Screenshots/Recordings

Before

Settings description specifically mentioned Ethereum Mainnet only

After

Settings description is now more generic to accommodate multiple supported networks

Pre-merge author checklist

• I've followed MetaMask Contributor Docs and MetaMask Mobile Coding Standards.
• 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 format if applicable
• I've applied the right labels on the PR (see labeling guidelines). 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.

[github-actions]

CLA Signature Action: All authors have signed the CLA. You may need to manually re-run the blocking PR check if it doesn't pass in a few minutes.

[github-actions]

Bitrise

❌❌❌ pr_smoke_e2e_pipeline failed on Bitrise! ❌❌❌

Commit hash: 49c1e58
Build link: https://app.bitrise.io/app/be69d4368ee7e86d/pipelines/139a7755-eafb-4ebc-aaed-dc91e4d7797f

Note

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Tip

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[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

Bitrise

❌❌❌ pr_smoke_e2e_pipeline failed on Bitrise! ❌❌❌

Commit hash: 74a5e85
Build link: https://app.bitrise.io/app/be69d4368ee7e86d/pipelines/28f5dac4-3ed3-4392-bd5f-faf45f6a1d57

Note

• You can kick off another pr_smoke_e2e_pipeline on Bitrise by removing and re-applying the Run Smoke E2E label on the pull request

Tip

• Check the documentation if you have any doubts on how to understand the failure on bitrise