The badge-deduplication helper was extracted from
InfoStandWidgetUserView in the prior commit; it's a pure (badges[]) =>
badges[] function that keeps slot indices stable by replacing duplicate
codes with empty strings. Coverage:
- empty input
- unique-only passthrough
- duplicate-replaced-with-empty
- falsy entries (null / undefined / '') normalized to ''
- first-occurrence-wins semantics
- order sensitivity (same multiset, different order -> different output)
simoleo89