Support serialization of Union types#44481

Draft

srnagar wants to merge 3 commits intoAzure:mainfrom srnagar:union-serialization

+647-23

Commits on Mar 3, 2025

Initial commit to support serialization of Union types
srnagar
committed

Commits on Mar 4, 2025

update unit tests
srnagar
committed

Commits on Mar 5, 2025

update serialization of list
srnagar
committed