//! # Companion example: prepend a bias/intercept column (matten-mlprep)
//!
//! Run: cargo run -p matten-mlprep --example mlprep_add_bias_column
//!
//! ## What this shows
//! Prepending a constant `1.0` column to a `[samples, features]` matrix — the
//! usual way to give a linear model an intercept term.
//!
//! ## Teaching points
//! - rows are samples; a new leading column of ones is added;
//! - the feature count grows by exactly one; the sample count is unchanged;
//! - deterministic, with no model state.
use Tensor;
use add_bias_column;