//! Shared error type for the pipeline stages.
//!
//! The stages orchestrate filesystem IO, JSON (de)serialization, and schema
//! validation, so a stage failure can originate in any of those. `PipelineError`
//! unifies them behind one `thiserror` enum (the library-side convention; the CLI
//! boundary maps it to `anyhow`).
/// A recoverable failure while running a pipeline stage.