Implement Basic Reverse Proxy Routing

[fuunshi]

Is your feature request related to a problem? Please describe.
The project currently lacks basic reverse proxy routing functionality. Incoming HTTP requests are not forwarded to the correct backend based on configuration, preventing core proxy use cases.

Describe the solution you'd like

• Start an HTTP server using hyper or axum
• Read routes from the parsed configuration
• Match incoming request paths to configured backends
• Forward the request to the backend and return the response to the client
• Add basic logging of requests and responses
• Write unit tests for route matching logic

Describe alternatives you've considered

• Using other Rust web frameworks like warp or actix-web but hyper/axum are preferred for their flexibility and ecosystem support.
• Implementing a custom matching algorithm, but using standard path matching should be sufficient for initial implementation.

Additional context
This is a foundational feature for the project. Logging and test coverage will help ensure reliability and ease of debugging.