Decouple widget displaying logic out of the datastore

## Feature Description

In #9548, we refactored the key metric widget rendering to use an additional callback. However, such callbacks are now being called in the datastore which can be decoupled as mentioned in the Code Review comments in PR #9581. This issue is a follow up to implement those CR comments and any other potential improvements.

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## Acceptance criteria

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## Implementation Brief

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### Test Coverage

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## QA Brief

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## Changelog entry

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