Add HTTP Proxy Support with TLS for Upstream Connections

[hippalus]

Add HTTP Proxy Support with TLS for Upstream Connections

Objective

Implement an HTTP proxy that supports HTTP/2 by default but can downgrade to HTTP/1.1.
Add TLS client support for upstream connections, allowing re-encryption when connecting to secure upstream servers (e.g., HTTPS, MQTT over TLS or any TCP over TLS).

Tasks

• HTTP Proxy Implementation
• TLS Client for Upstream Connections
• Support HTTP/2 with the ability to downgrade to HTTP/1.1 based on client capabilities
• Support features like header manipulation, filtering, and rate limiting