feat: add receive schemas to check-docks worflow

[Gara-Dorta]

This PR adds the receive schemas to the check-docs.yml workflow. Here is a successful run of it https://github.com/Gara-Dorta/signal-cli-rest-api/actions/runs/26340800873

This is a follow up of #849 and #842, they got merged at the same time but they have this interaction with each other.

[Gara-Dorta]

I'm not too happy with getting the signal version like this. I think a better approach is to have a separate file in the repo and read it from there. Like how signal-cli has the lib version in this file https://github.com/AsamK/signal-cli/blob/master/libsignal-version

However to keep with single responsibility PRs. If that is something you'd like, I'd do it in a separate one.

[bbernhard]

Thanks - looks good to me! But I think it might make sense to keep this PR open until your signal-cli CI PR is merged. :)

[Gara-Dorta]

I think so too. However, getting code merged in signal-cli is a slow process. So if you need to make a release in the meantime, I've made new releases in my fork https://github.com/Gara-Dorta/signal-cli/releases so that this workflow and the one #842 don't crash and download the correct json files for each signal-cli version.

[bbernhard]

Hmm...what if we check out signal-cli and build the json schemas with ./gradlew jsonSchemas directly in this CI job? 🤔

[Gara-Dorta]

If we are building it ourselves, I think it makes more sense to add it as a new artifact output in https://github.com/bbernhard/signal-cli-native-builds/blob/master/.github/workflows/build.yml than do it here.

When working on #842 I gave a quick try. However, after a few minutes of coding it felt silly to duplicate the work in there when I could simply publish a release in my signal-cli fork by uploading a tag.