Add Ethereum RPC fallback utility with multiple endpoint support

[Copilot]

This PR implements a robust fallback utility for Ethereum RPC endpoints to improve reliability when querying blockchain data. The current walletVerify.js uses a single RPC endpoint, which creates a single point of failure.

What's Changed

New Utility Module (utils/rpcFallback.js)

• Multi-endpoint fallback logic: Automatically rotates through 5 RPC endpoints when one fails
• Robust error handling: Validates Ethereum addresses using Web3.js native validation
• Consistent logging: Follows project's emoji-coded logging format with timestamps
• Comprehensive error reporting: Provides detailed information about all failed attempts

Updated Integration

• Enhanced walletVerify.js: Now uses the fallback utility instead of a single endpoint
• Backward compatibility: Maintains existing function signatures and behavior
• Proper module exports: Easy to integrate with other parts of the system

Key Features

const { getBalanceWithFallback, logError } = require('./utils/rpcFallback');

// Automatically tries multiple endpoints
const balance = await getBalanceWithFallback('0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045');

Error handling example:

🚨 [2025-09-17T23:17:48.630Z] RPC Endpoint Failed: https://endpoint1.com - Connection timeout
🔄 Attempting RPC endpoint 2/5: https://endpoint2.com

Benefits

• Improved reliability: No longer dependent on a single RPC provider
• Better error visibility: Clear logging of which endpoints fail and why
• Production ready: Can easily replace demo URLs with actual API keys
• Minimal changes: Drop-in replacement requiring no changes to calling code

The utility includes 5 example RPC endpoints that can be replaced with actual URLs as needed. All endpoint failures are logged with detailed error information, and the system only fails when all endpoints are unreachable.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• blockchain.googleapis.com
  • Triggering command: node /tmp/testRpcFallback.js (dns block)
  • Triggering command: node /tmp/testWalletVerify.js (dns block)
  • Triggering command: node /tmp/comprehensiveTest.js (dns block)
• eth-mainnet.alchemyapi.io
  • Triggering command: node /tmp/testRpcFallback.js (dns block)
  • Triggering command: node /tmp/testWalletVerify.js (dns block)
  • Triggering command: node /tmp/comprehensiveTest.js (dns block)
• ethereum.publicnode.com
  • Triggering command: node /tmp/testRpcFallback.js (dns block)
  • Triggering command: node /tmp/testWalletVerify.js (dns block)
  • Triggering command: node /tmp/comprehensiveTest.js (dns block)
• mainnet.infura.io
  • Triggering command: node /tmp/testRpcFallback.js (dns block)
  • Triggering command: node /tmp/testWalletVerify.js (dns block)
  • Triggering command: node /tmp/comprehensiveTest.js (dns block)
• rpc.ankr.com
  • Triggering command: node /tmp/testRpcFallback.js (dns block)
  • Triggering command: node /tmp/testWalletVerify.js (dns block)
  • Triggering command: node /tmp/comprehensiveTest.js (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

This pull request was created as a result of the following prompt from Copilot chat.

Add a utility module that implements fallback logic for Ethereum RPC endpoints. The module should attempt to retrieve the balance of a given Ethereum address by rotating through a list of endpoints. If one endpoint fails, it should proceed to the next, logging errors for each failure, and only returning the balance from the first successful endpoint. If all endpoints fail, it should throw an error. The utility should export a function getBalanceWithFallback(address) and a logError helper. Example endpoints provided in the code can be replaced with actual RPC URLs as needed.

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[xpertforextradeinc]

Looks good to me. Thanks for updating the .gitignore with Node.js dependencies and adding clear documentation for the RPC fallback utility. These changes improve both maintainability and clarity. ✅