v1.0.0: feat: socket - a simple TCP server framework for Go

Features:
- TCP server with context-based graceful shutdown
- Custom Codec interface for message encoding/decoding
- Asynchronous read/write loops with errgroup
- Heartbeat/deadline support for connection health
- Flexible error handling with ErrorAction (Disconnect/Continue)
- Structured logging with slog
- Functional options pattern for configuration
- GitHub Actions CI/CD workflow