- replace gRPC/DTLS tunnel paths with TLS + yamux transport
- remove legacy protocol, protobuf, DTLS, and proxy implementations
- simplify server and client entrypoints around yamux
- update configuration, metrics, API, and architecture documentation
- add bidirectional yamux session tests
- verify with go test ./...
- 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.
dalbodeule