Load js app data in controller

What does this MR do?

This change request is a continuation of a conversation started in !22465 (diffs, comment 284486028)

It extract the data that is loaded for the client side application in the controller so that each piece of data that is loaded can be tested.

#14061 (closed)

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Does this MR meet the acceptance criteria?

Conformity

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• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
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