v3.2.1

Fixed

• Duplicate UnmarshalJSON — codegen skips emitting UnmarshalJSON for types that already have one (from importer)
• Importer discriminator detection — requires field in ≥2 variants, prefers most-common field. Fixes wrong discriminator (detail vs type) on unions like InputContent
• Integer type fidelity — preserves int vs int64 in IR for correct constructor params
• Constructor nullable params — *T fields correctly unwrap to T param type (was producing **T)