- Add ProxyError enum with IntoResponse for error handling (400, 404, 502, 504)
- Implement proxy header injection: X-Real-IP, X-Forwarded-For (replaced, not appended), X-Forwarded-Proto
- Implement hop-by-hop header removal for both request and response headers
- Implement request forwarding via shared hyper::Client with HTTP and HTTPS support
- Add ProxyState with http_client and https_client instances shared via axum State
- Add per-site timeout overrides using tokio::time::timeout
- Add HTTPS upstream support with system native TLS root certificates
- No Server or Via headers added to responses
- Host header preserved as-is
- Add unit tests for header injection, hop-by-hop removal, and URI building
- Add integration tests for proxy forwarding, hop-by-hop removal, and 502 on unreachable upstream
- Add TokenBucket with nodelay semantics (nginx limit_req burst nodelay)
- Per-IP rate limiting: IPv4 /32, IPv6 /64 prefix normalization
- DashMap for concurrent access, ArcSwap for lock-free config reads
- Background eviction task for stale entry cleanup
- 429 response with plain text body, RATE_LIMIT log prefix
- Config reload adopts new rate/burst on next request without clearing state
- Unit tests for bucket algorithm and IPv6 normalization
- Integration tests for 429 responses and per-IP independence
- Add health.rs module with start_health_check_listener() that binds to
127.0.0.1:{health_check_port} and serves GET /health returning 200 OK
with empty body
- Add health_route() in proxy/handler.rs for HTTPS listener fallback
- Add port conflict detection in config validation: health_check_port
must not conflict with listener ports on 127.0.0.1/localhost/0.0.0.0
- health_check_port = 0 disables the separate listener (handled at call
site)
- Add unit and integration tests for health check functionality
- Add [lib] target to enable integration test imports
- Add rcgen and reqwest dev-dependencies for TLS and HTTP test helpers
- Create src/config/test_fixtures.rs with test_static_config() and test_dynamic_config()
- Create tests/ with integration tests, HTTP test helper (TestUpstream), and TLS test helper (SelfSignedCert)
- Add Clone derives to StaticConfig and related structs for test fixture construction
- All existing tests continue to pass
