+ Adds new commands for managing boxes, environment variables, and running the server.
* The command structure is greatly expanded to improve user experience and coverage for core service functionalities.
- Add `cmd/main.go` with a new `warpbox` root command and `run` subcommand
- Support `--addr` flag (default `:8080`) and delegate startup to `server.Run`
- Initialize Go module and dependencies (cobra, gin) via `go.mod`/`go.sum` to enable building the new CLI entrypointfeat(cli): add cobra-based CLI to run WarpBox server
- Add `cmd/main.go` with a new `warpbox` root command and `run` subcommand
- Support `--addr` flag (default `:8080`) and delegate startup to `server.Run`
- Initialize Go module and dependencies (cobra, gin) via `go.mod`/`go.sum` to enable building the new CLI entrypoint
