//! Proof objects and TSTP output for automated theorem proving.
//!
//! After a refutation is found, this crate:
//!
//! 1. **Extracts** the proof DAG by tracing back from the empty clause
//! through `ClauseSource::Inference` parent pointers ([`extract`]).
//! 2. **Formats** the proof in TSTP format for verification by external
//! tools ([`tstp`]).