Investigate rate limiting (account + IP keyed) due to security probing

## Summary
Investigate implementing or reviewing rate limiting mechanisms keyed off both account and IP address due to security probing activity.

## Details
We are experiencing security probing that requires rate limiting controls. The rate limiting should be keyed off both:
- Account identifier
- IP address

## Tasks
- [ ] Assess current rate limiting implementation
- [ ] Determine if account + IP keyed rate limiting is in place
- [ ] Identify any gaps or improvements needed
- [ ] Implement or enhance rate limiting as necessary
- [ ] Test rate limiting behavior

## Priority
High - Security related