optimizer: Switch to `Some{}` in PersistentDict optimized generics (#61053)
This fixes #53584 by switching the return type of the KeyValue optimized
generics interface to allow any one-field struct, not just `Tuple`. In
particular, the persistent dict implementation uses `Some{V}`. This
makes a material difference because Tuple{Any} does not (currently) have
special ABI support, while Some{Any} does.
Written by Claude