The right needs to be wrapped in parens or we cannot accurately match its
span to just the RHS. For example, the span in `e = $event /*0,10*/` is ambiguous.
It could refer to either the whole binary expression or just the RHS.
We should instead generate `e = ($event /*0,10*/)` so we know the span 0,10 matches RHS.
This is specifically needed for the TemplateTypeChecker/Language Service
when mapping template positions to items in the TCB.
PR Close#39143
4ede190571