Feature: Manifest Validation

[constraintAutomaton]

Feature: Manifest Validation

This PR introduces manifest validation that runs before package installation. Additionally, all packages are now required to specify a license.

Changes

• Added pre-installation manifest validation
• Enforced license requirement for all packages

Future Work

• Add CLI flag to validate manifests without performing installation (e.g., --validate-only)
• Better handling of multiple licenses

closes #23

[bakaq]

Looks good. I've pointed out some places that can improve in terms of purity. Validation of the manifest is something that could certainly be done in just pure and monotonic Prolog, though it's certainly very annoying without something like Qupak.

I also really like the enforcement of licenses.

[bakaq]

Nice integration of Qupak! There is still some cleaning up of the module-related stuff left though.

I've put some background on operators in Qupak and why we might still want to have them, and some suggestions where the code can be cleaned up a bit.

[bakaq]

Looks good to me. Let's get this in!