feat: Autocompletion on pixi

Pixi has implemented support for shell autocompletion scripts a few weeks ago in (https://github.com/prefix-dev/pixi/pull/3219 and https://github.com/prefix-dev/pixi/issues/2366)

To take advantage of this feature, a package needs to install autocompletion files in one of these directories depending on the user's shell:

• share/bash-completion/completions
• share/zsh/site-functions
• share/fish/vendor_completions.d

I tested this with both Bash and Zsh on macOS, using the attached scripts (unzip in the root of your pixi workspace) and it's working great. What's missing is just RoboStack installing these files automatically as part of the distribution.

Is this the correct repo to discuss how to possibly get this merged? We encountered this as part of a university course on ROS we are teaching, so we'd really benefit from a fix. I can send a pull request after we define how you'd like to approach this.

Thank you!

ros-autocompletion.zip

Start by reviewing the repository's package recipes and the three autocompletion directories listed in the issue. Determine how distribution files are installed for Bash, Zsh, and Fish, then verify that the completion files are present and usable after installation.