feat: auto-publish infoview

[joneugster]

Automatically publish infoview and infoview-api on npmjs if the version changed.

[joneugster]

This is a first draft, containing the modifications to publish the infoview from CI.

One needs to create an NPM access token and add it as github secret NPM_TOKEN.

This does not yet contain any version number management.

I have a hard time testing this, only did so for @leanprover/infoview but not for the infoview-api yet.

[joneugster]

@mhuisi I think this is now one of the simplest versions I could think of. on a new release, if the package version of infoview or infoview-api changed, it will publish the new version to npmjs.

Using e.g. npm --workspace=lean4-infoview version patch to bump the version is still required to happen manually.

It does not necessarily need to be coupled to the release schedule of the VSCode-extension, but I figured doing so ensures that only maintainers will trigger the publishing (at defined steps of the procedure) and not by accident.

Note: in this CI run you can see how it tries to publish infoview but just prints a note for infoview-api. The npm error seems to be the way the say "authentification failed"

[Vtec234]

Haven't tested it but looks good in theory!