[FR]: add `rules_license` providers to NPM imported packages

### What is the current behavior?

There is no integration between `aspect_rules_js` and `rules_license`

### Describe the feature

It would be useful if items that are imported from `package.json` could return a `LicenseInfo`. This would allow other tooling built to use `rules_license` to be used with JS-based projects (eg. it might be possible to generate an SBOM from this information)

Start by tracing how aspect_rules_js imports items from package.json and review the rules_license integration points for producing LicenseInfo. Done means imported NPM package items expose LicenseInfo that other rules_license tooling can consume, such as for SBOM generation.

Written by the indexing model from the issue text.