Clean up cloud_chat

[Dosant]

Summary

Close https://github.com/elastic/kibana-team/issues/1017

This PR removes the unused Cloud Chat functionality from Kibana. The chat was not used for some time. Moreover, we've seen some issues with it where users saw it when it wasn't expected. Given the absence of automated tests and the fact that the feature is no longer needed, we are removing it to improve the overall maintainability and reliability of the codebase. This will also decrease the amount of code loaded for trial users of Kibana in cloud making the app slightly faster.

[github-actions]

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Metrics [docs]

Module Count

Fewer modules leads to a faster build time

id	before	after	diff
cloudChat	35	-	-35

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
cloudChat	7.3KB	-	-7.3KB

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
cloudChat	14.1KB	-	-14.1KB

Unknown metric groups

async chunk count

id	before	after	diff
cloudChat	2	-	-2

History

• 💔 Build #238387 failed ac18f8e

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