The user-facing setter: writes the ref (via writeScrRef) AND records the change in the
scroll group's reference history. Reference-history navigation itself does NOT go through here —
it calls writeScrRef directly, since its stacks already reflect the move.
Parameters
scrollGroupId: undefined|number
scrRef: SerializedVerseRef
OptionalsourceProjectId: string
Project whose versification scrRef is expressed in. undefined =
unknown / canonical English.
See IScrollGroupRemoteService.setScrRef
The user-facing setter: writes the ref (via writeScrRef) AND records the change in the scroll group's reference history. Reference-history navigation itself does NOT go through here — it calls writeScrRef directly, since its stacks already reflect the move.