Improve npmx custom badge

[Gugustinette]

We can already render classic version badge using the /api/registry/badge/[...pkg] route :

We could go further and provide a parameterized route, which can display the data for any field available in npmx :

• License
• Install size
• Monthly/Weekly downloads
• Vulnerabilities
• Number of dependencies
• Last updated date

I might miss some fields, but that's the idea.

[trueberryless]

I'd like to play around with that! 👍