Update snakecase-keys dependency and clarify maintenance status

[dana-blanc-healthy]

Hi,

I noticed that the postgrid-node-client package has a dependency on snakecase-keys@4.0.2, which is now deprecated. Running npm install produces the following warning:

npm WARN deprecated snakecase-keys@4.0.2: This version contains a breaking change for users depending on unspecified behaviors with repeated capital letters. See https://github.com/bendrucker/snakecase-keys/issues/47. Please upgrade to the identical 5.0.0 release instead.

Would it be possible to update this dependency to snakecase-keys@5.0.0 or later to address the warning?

Additionally, I would like to confirm whether this project is actively maintained. If not, it would be helpful to know so we can consider alternative approaches or forks.

Thank you!