Michael Schimmel
f35606616b
Refactor the optimizer to use a Purity enum instead of a boolean for tracking function purity. This allows for a more granular representation of purity: - `Impure`: Functions with side effects. - `SideEffectFree`: Functions without side effects but may not be deterministic (e.g., `now()`, `random()`). - `Pure`: Functions without side effects and are deterministic. This change enhances the optimizer's ability to perform more aggressive optimizations by accurately determining function purity.