//! State model — MemoryState, StateSchema, Ref, Cell.
//!//! Mirrors Python `operonx/core/states/`.
//!//! Note: Rust's `ref` is a reserved keyword. The file stays `ref.rs` (matching
//! Python's `ref.py`) but the module identifier is `ref_` — see §3a.7.
pubmodcell;#[path="ref.rs"]pubmodref_;pubmodschema;pubmodstate;