feat: allow Linux dependencies to be specified via a file path

[kevinaboos]

This makes it possible to dynamically generate the list of dependencies for Linux Debian and pacman package formats.

Fixed a small documentation bug in PacmanConfig.

Notes

We needed this feature in Project Robius to relieve the app dev from the burdens of:

1. figuring out which dependencies their app binaries need.
2. having to keep that list up to date when adding or removing dependencies from their app, which typically is only done at the Rust crate level (rather than the Linux native package/library level).

This changeset has been tested to work for us on Ubuntu LTS 20.04, 22.04, and 24.04, on both aarch64 and x86_64.

Question: I modified the crates/packager/schema.json file by hand -- not sure if that's correct or if it's generated automatically. It appears that bindings/packager/nodejs/schema.json was indeed auto-generated; not sure if that needs to be committed too. Please advise, thanks!

[amr-crabnebula]

Question: I modified the crates/packager/schema.json file by hand -- not sure if that's correct or if it's generated automatically. It appears that bindings/packager/nodejs/schema.json was indeed auto-generated; not sure if that needs to be committed too. Please advise, thanks!

It should be automatically generated if your IDE runs the build script of config-schema-generator crate, if not, you can manually build it using cargo b -p config-schema-generator and it will generate the schemas.

[kevinaboos]

ah sorry, i had forgotten to run rustfmt. Fixed now.

[amr-crabnebula]

Thank you

[kevinaboos]

Thanks! Shall I go ahead and add env var support too?

[amr-crabnebula]

That would be awesome, thanks