New API and feature

• API: dateRangeOptions()
• Feature: AltDateWidget supports relative Years and reversed order of Year choices

@rjsf/antd

• Updated AltDateWidget to use the new dateRangeOptions() function in utils to support relative Years and reversing the order of the Year choices

@rjsf/chakra-ui

• Updated AltDateWidget to use the new dateRangeOptions() function in utils to support relative Years and reversing the order of the Year choices

@rjsf/core

• Fixed case where readOnly from a JSON Schema was not applied in SchemaField (#4236)
• Updated AltDateWidget to use the new dateRangeOptions() function in utils to support relative Years and reversing the order of the Year choices

@rjsf/utils

• Added a new dateRangeOptions() function to implement relative Years in (via negative ranges) and reversing the order of the Year choices

Dev / docs / playground

• Added documentation for the new dateRangeOptions() function as well as showing examples of using relative Years and reversed Year ordering