s&box SpawnerWeapon serializes its ISpawner payload as "type:data" string (e.g.

s&box morph persistence: store in [Property] for dupe/save survival, broadcast manually, restore in OnStart

s&box Duplicator: serialize contraptions in selection space (not world space) for correct paste orientation

s&box SaveSystem: [Sync]-only properties need separate snapshot/restore — they are not captured by scene diff

s&box: JSON serialization with Sandbox.Json — handles engine types that System.Text.Json misses