fix: update transaction and balance cache when balance changes are detected

[pedroanastacio]

Description

• The balance and transaction cache was only updating after a few minutes, which meant that the UI had incorrect data until the cache was updated.

Summary

• Adds endpoint (/user/check-balances/) to check balances of all predicates related to user and emit socket event if the cached balances are different from the blockchain balance
• Adds endpoint (/predicate/check-balances/:predicateId) to check balances of the given predicate and emit socket event if the cached balances are different from the blockchain balance
• Adds socket events to notify the UI when the balance and transaction caches are updated
  • BALANCE_OUTDATED_USER
  • BALANCE_OUTDATED_PREDICATE
• Adds util function (compareBalances) to compare cached balances with blockchain balances

Checklist

• I reviewed my PR code before submitting
• I ensured that the implementation is working correctly and did not impact other parts of the app
• I mentioned the PR link in the task

[guimroque]

Code Review - Summary

What was done

• Added two new endpoints to check balance differences between cache and blockchain:
  • /user/check-balances/ - checks all predicates for a user
  • /predicate/check-balances/:predicateId - checks specific predicate
• Added socket events BALANCE_OUTDATED_USER and BALANCE_OUTDATED_PREDICATE to notify UI when cache is updated
• Added compareBalances utility function to detect balance changes
• Added getBalancesFromBlockchain method to ProviderWithCache for direct blockchain queries
• Implemented cache invalidation and update logic when balance changes are detected

Positive Points

• Good separation of concerns with dedicated service methods
• Proper error handling with try/catch blocks
• Uses existing authentication and permission middlewares
• Implements proper TypeScript interfaces
• Good use of Promise.all for concurrent balance checks
• Includes safety limit (MAX_PREDICATES_TO_CHECK_BALANCE = 50)
• Proper cache invalidation strategy

Issues Found

• Missing input validation for predicateId parameter
• Potential performance issues with concurrent database queries
• Console.log statements should be removed
• Missing error context in some catch blocks
• Socket event naming inconsistency

Total comments: 5 (1 critical, 3 important, 1 suggestion)

[guimroque]

LGTM! ✅

Previous issues have been fixed. Code approved.