Allow programmatic usage of SBOM builder #1142

Is your feature request related to a problem? Please describe.

I would like to use this tool for SBOM generation of our npm projects for further processing. Calling it via CLI is not the most convent option of doing this. Right now importing of BomBuilder, TreeBuilder, etc. is explicitly prohibited https://github.com/CycloneDX/cyclonedx-node-npm/blob/main/package.json#L87

Describe the solution you'd like

It would be great to have a public API for SBOM building