- Add createRateLimit(maxAttempts, windowMs) factory function
- Rewrite rateLimit export to delegate to factory (backward compatible)
- Keep shared store, getClientIp, cleanup, and _resetForTesting unchanged
- Add createRateLimit factory test suite with 5 test cases
- All existing rateLimit middleware tests still pass
Implement in-memory rate limiter with 5 attempts per 15-minute window per IP address. Protects brute-force attacks on credential endpoints.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>