Improve initial load of calculated expression

[FikriMilano]

IMPORTANT: All PRs must be linked to an issue (except for extremely trivial and straightforward changes).

Fixes #2519

Description
On initial load of forms:

1. Iterate all items with calculated expression
2. Evaluate the calculated expression
3. Update the QR item answer

Alternative(s) considered
N/A

Type
Improvement

Screenshots (if applicable)

Checklist

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[MJ1998]

What if there is an item (maybe display item) which is dependent on the initial calculated expression ?

[FikriMilano]

@jingtang10 @MJ1998 this is ready for review

[FikriMilano]

@MJ1998 hmm, I might not understand what you're trying to say. Could you elaborate? And some examples.

Display item can't really depend on other items unless the display item is using cqf expression, display item has no answer, so it cannot use calculated expression.

[jingtang10]

This is really great optimization! Thanks @FikriMilano!

This is not your code, but I've just noticed in the file ExpressionEvaluator.kt function evaluateCalculatedExpressions the use of updatedQuestionnaireResponseItemComponent is actually wrong. What should be passed as the %context should be the corresponding questionnaire response item of the questionnaire item with calculated expression that is affected. Can you please fix that in this PR? I think what you can do is to actually just pass a null value there and add a comment to say something like "to properly use %context we will need to find questionnaire item and questionnaire response item pairs etc.. but we won't do that now." You can then just simplify that function signature.

[FikriMilano]

@jingtang10 this is ready for review

[jingtang10]

Thanks for the PR @FikriMilano great job!