Add an option to show the version of the CLI

[tschaffter]

I wanted to report the version of the CLI installed in my environment in another ticket, then realized that the option --version is not implemented.

$ devcontainer --version
Specify a command
devcontainer <command>

Commands:
  devcontainer open [path]   Open a dev container in VS Code
  devcontainer build [path]  Build a dev container image

Options:
  -h, --help               Show help  [boolean]
      --disable-telemetry  Disable telemetry  [boolean] [default: false]

[joshspicer]

It appears you have the older 'vscode devcontainer CLI' installed on your machine. Despite the name it is not the same as the source code in this repo.

I suggest removing that command and installing the CLI from this repository. You can do so with npm:

npm install -g @devcontainers/cli

We're aware that two tools with the same name is confusing. I imagine the goal is to either remove the "vscode devcontainer CLI" completely, or forward commands to a vscode-specific build of the OSS CLI (this repo).

@bamurtaugh @chrmarti @Chuxel - We should do something about this to avoid future confusion :)

[bamurtaugh]

Thanks for the tag @joshspicer and for opening this issue @tschaffter!

@alexdima and @chrmarti have been working on forwarding from the previous devcontainer CLI to the new OSS devcontainer CLI.

The built-in CLI devcontainer (or devcontainer-insiders for VS Code Insiders) of the Remote-Containers extension now forwards to the built-in open source CLI. The open command and the previous CLI arguments for the build command are also supported.

@chrmarti @alexdima is there another scenario we'll still need to cover where users may install / use the older CLI in another way (not from Remote-Containers)?

[chrmarti]

There is a --version option now, but I need to fix where it looks up the version (currently goes to the extension's package.json, but we want the CLI's package.json to be used).