[ddebowczyk92]

Reject unexpected null results during asynchronous split initialization with a descriptive exception instead of an ArrayList.addAll() NPE. Include the source class in initialization errors while preserving the original cause.

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[ddebowczyk92]

assign set of reviewers

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R: @chamikaramj added as fallback since no labels match configuration

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[ddebowczyk92]

@Abacn Hey, would you mind taking a look?

[chamikaramj]

Thanks for the fix.