Allow using types without initializing entire package

No files or tests are named. Start by inspecting the package configuration and type exports, then determine how the types can be consumed without install scripts or the Node.js 24 requirement; done means CI workflow authors can import the types independently.

As a developer, I want to use github-script in my CI workflow. With large scripts, it becomes necessary to move from inline usage to importing from a separate file (i.e. script.ts). When developing, I want to make sure type safety is followed, so I want to import the typing provided by github-script.

github-script has multiple issues that make this nearly impossible in my dev environment:

• I don't allow install scripts, but @actions/github-script@7.0.1 has them;

The git-hosted package "@actions/github-script@7.0.1" needs to execute build scripts but is not in the "onlyBuiltDependencies" allowlist.

• github-script wants node>=24. I'm in the process of upgrading the environment, but there are some blockers. If I only want types, I shouldn't need node>=24.

Could the types be released as a separate package, making it easier to develop github-script CI flows without having to trust a blackbox install scripts or having the latest node.