🚀 Bundle completions in the packages such as .deb

[thernstig]

https://github.com/sharkdp/bat bundles completions in e.g. .deb files. https://fishshell.com/docs/current/completions.html#where-to-put-completions describes that this can be put at /usr/share/fish/vendor_completions.d/.

Here is an example for bat:

> fd bat /usr/share/fish/
/usr/share/fish/vendor_completions.d/bat.fish

It would be cool if delta could do this as well. When using the Fish shell, sourcing completions directly in config.fish is generally not recommended. So the best way to get proper completions with each update of delta would be to have them included with the installation.