chore: add token balances in getSupportedTokens

[VGabriel45]

Summary

Added a fetch for token balance in getSupportedTokens method which is returning supported erc20 tokens for paymaster payments. This method output will now also contain token balance of the smart account.

Created a new method getTokenBalance() which is similar to getTokenBalanceInfo() (which has been renamed from getBalance()), the scope of this new method is to fetch only the token balance and nothing more.

Change Type

• [ ] Bug Fix
• [ ] Refactor
• [x] New Feature
• [ ] Breaking Change
• [ ] Documentation Update
• [ ] Performance Improvement
• [ ] Other

Checklist

• [x] My code follows this project's style guidelines
• [x] I've reviewed my own code
• [x] I've added comments for any hard-to-understand areas
• [ ] I've updated the documentation if necessary
• [x] My changes generate no new warnings
• [x] I've added tests that prove my fix is effective or my feature works
• [x] All unit tests pass locally with my changes
• [x] Any dependent changes have been merged and published

---

PR-Codex overview

Focus: Enhancing token balance handling and adding balance property to tokens.

Detailed summary

• Added balance property check for tokens in tests
• Modified getBalance method in BiconomySmartAccountV2
• Updated tests for fetching token balances
• Added balance property to token info in feeQuotesResponse mapping

✨ Ask PR-Codex anything about this PR by commenting with /codex {your question}

[github-actions[bot]]

size-limit report 📦

Path	Size
core (esm)	51.74 KB (+0.33% 🔺)
core (cjs)	56.41 KB (+0.06% 🔺)
smartAccount (tree-shaking)	50.78 KB (+0.05% 🔺)
bundler (tree-shaking)	2.27 KB (0%)
paymaster (tree-shaking)	2.19 KB (0%)