chore: add .wallet_info.txt to gitignore for security

- Protect wallet information from being committed to git
- Wallet configured for Phase 1 deployment
- Using public Arbitrum RPC endpoints

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

.gitignore

@@ -83,3 +83,4 @@ anvil_fresh.log
 arbitrage_detection_test.log
 ARBITRAGE_DETECTION_TEST_RESULTS.md
 /tmp/mev-bot-test.log
+.wallet_info.txt