When a worklet module is fetched, e.g. via CSS.paintWorklet.addModule(), the fetched resource is now available in resource timing and in PerformanceObservers. window.performance.getEntries() or window.performance.getEntriesByType("resource") would also show worklet resources, which were not present there before despite being loaded.
Resource timing should reflect all the available loaded resources, and worklets are not fetched in any special way. This aligns them with reporting of worker scripts, that are already reported to resource timing.