chore: keep pkarr js package version in sync with rust version

[SHAcollision]

Ideally we should have some sort of automated process ,as well as lint/built checks, for the js bindings. If we really hate this extra entropy so much here, we should eject the js bindings to a new repository and enable the GH workflows there to ensure a new release for rust leads to a new release for JS.

https://www.npmjs.com/package/@synonymdev/pkarr
https://github.com/pubky/pkarr/blob/main/bindings/js/Cargo.toml

At the moment there has been a few Pkarr rust releases (from 3.8.0 to 5.0.0) that have not been translated into new npmjs releases.

I also think it would be less confusing if the package.json version matches the rust version 5.0.0 as a mean to display feature parity and compatibility.