[Feature Request] Autocompletion for devcontainer cli commands

It would be helpful if the commands in the terminal will autocomplete.

I would like to see this feature added.

For example:

`devcontainer feature test --skip-s`

when hitting tab it should autocomplete to `--skip-scenarios`

Start at the devcontainer CLI command definitions and trace how `devcontainer feature test` exposes the `--skip-scenarios` option. Determine where shell completion is configured or generated, then verify that typing `devcontainer feature test --skip-s` and pressing Tab completes to `--skip-scenarios` and works for the other CLI commands.

Written by the indexing model from the issue text.