- 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 `StatusGatewayTimeout` (504) for server-side timeouts between HopGate and backend.
- Implemented 504 error page with multilingual support.
- Enhanced `bufio.Reader` usage in JSON decoding to prevent "dtls: buffer too small" errors for large payloads.
- Applied request handling improvements for control domain and timeout scenarios.
- Implemented custom HTML templates for `400`, `404`, `500`, and `525` error pages with multilingual support.
- Added embedded file system for error page templates and assets.
- Introduced fallback mechanism to serve minimal plain text for missing error templates.
- Integrated TailwindCSS for styling error pages, with a build script in `package.json`.