feat: Parse prom data to JSON

[CyberCyclone]

I haven't seen any way to do this, but is it possible to use this package to parse prometheus data into JSON data? If not, is such an option able to be included?

[zbjornson]

Check out #470 / #471 -- are those what you have in mind? If so, feel free to test out and review #471.

[Filipoliko]

I think that #470 / #471 implement something a little bit different. I think that the author of this issue would like a feature to parse prometheus text format (let's say you want to scrape some 3rd party components /metrics route and process the data), but the PR implements a different export format for the prometheus metrics, which seems like a little bit different scenario.

I found an NPM package that seems to implement this, but it does not seem to be actively maintained and there seem to be some issues.

We are already using prom-client package in many projects and we could use this feature also. Is there any consideration to implement this? Are you open to PRs?