[Move @kbn/config-schema to server] actions

[afharo]

Summary

Part of #189476.

We want to avoid @kbn/config-schema from leaking to the browser, and this plugin is using it outside the ./server directory.

I cannot find this code being imported in the UI, so I don't expect it to have any impact on bundle metrics, but this PR is still useful to avoid potential future leaks.

For maintainers

• This was checked for breaking API changes and was labeled appropriately

[elasticmachine]

Pinging @elastic/response-ops (Team:ResponseOps)

[kibana-ci]

💚 Build Succeeded

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• Commit: a6070b2

Metrics [docs]

✅ unchanged

History

• 💔 Build #231201 failed e388fa7

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

[szwarckonrad]

@afharo
Apologies, it seems this PR slipped through the cracks. Would you still like us to take a look at it?

[afharo]

@szwarckonrad, thanks! Let me move it to draft until I resolve the conflicts and will get back to you

[elasticmachine]

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[szwarckonrad]

@afharo
I'm doing some spring cleaning of my GitHub assignments, feel free to reassing me once you move it off the draft :)