- Introduced Prometheus metrics tracking for DTLS handshakes, HTTP requests, and proxy errors.
- Defined counters and histograms with labels for detailed observability.
- Registered metrics via `MustRegister` during server initialization.
- Added `/metrics` endpoint protected by host domain filtering.
- Updated HTTP handler to capture request metadata and record metrics.
- Integrated metrics tracking for DTLS handshake processes and various error conditions.
- Updated `go.mod` and `go.sum` with Prometheus client dependencies.
