fix: version and readme alpha note

[matthewkeil]

Small update so the version is correct when the das branch gets merged to main. Don't want to accidentally publish to the wrong version. Also removed the note about alpha versions. Wont get published until that is no longer true

[matthewkeil]

@jtraglia I saw PR #428 and the node bindings will need to be v4.0.0 for the DAS work. Because the alpha version got released accidentally there is no way to revert to v3.X.X... the v4.0.0-alpha.0 version will always be the landing screen for c-kzg because its the largest according to semver. I released a v4.0.0-alpha.1 with the code for default trusted setup a couple of days ago to just get rid of that deprecation warning banner in case anyone sees the package website. @g11tech and I have decided to go with v4.0.0 as the official version with the DAS code once that gets released and is merged to main. So the update in #428 is not going to work. This PR should get merged into the das branch to update that.

[jtraglia]

go with v4.0.0 as the official version with the DAS code once that gets released and is merged to main.

Why are we doing this now? We are months away from merging this into main. What will removing "alpha" change exactly? Are you planning to make a v4.0.0 release soon? Having "alpha" in the version name is the sole reason I was semi-okay with the v4 release in the first place. The das branch contains unaudited code which should not be used in production. If you remove "alpha" and remove the note at the top, what's to prevent someone outside of this circle from knowing that this version should not be used yet?

So the update in #428 is not going to work.

Why won't #428 work exactly? You can still make v3 releases, no? It not being at the top isn't that big of a deal.

[matthewkeil]

Closing and will reopen when the das branch merged to main