feat(api): add endpoint for user integration status (close #2861)

[AiraNadih]

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• I have tested my changes
• There is no breaking changes
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[fguillot]

if you add a new API endpoint, then it would be nice to add the corresponding function in the client package with an integration test.

[AiraNadih]

Oh, sorry, I forgot to update the client package and integration tests.