feat(core): faster YAML and JSON parser

[bzp2010]

Description

Replace the yaml library with js-yaml, which provides at least an order of magnitude performance improvement.
(2.85MB document, 1.3s => 0.19s)

We now explicitly provide JSON input support.
We used to use the yaml to provide fallback handling for JSON, but it was very slow. Now we've moved to using nodejs' built-in JSON.parse function, which uses the simdjson library under the hood. It's two orders of magnitude faster than using yaml's fallback strategy for JSON.
(2.39MB document, 1.17s => 0.03s)

To benefit from faster JSON parsing, you need to specify files with a .json extension. Files parsed with other extensions still use the fallback strategy of the js-yaml library.

Checklist

• I have explained the need for this PR and the problem it solves
• I have explained the changes or the new features added to this PR
• I have added tests corresponding to this change
• I have updated the documentation to reflect this change
• I have verified that this change is backward compatible