//! Self-supervised learning (SSL) methods for vision backbones.
//!
//! Provides:
//! - **`dinov2`**: the DINOv2 self-distillation recipe (Oquab et al. 2023),
//! combining the image-level DINO objective (Caron et al. 2021) with the
//! patch-level iBOT masked-image-modelling objective (Zhou et al. 2022) — a
//! ViT backbone returning `[CLS]` + patch tokens, a weight-normalised
//! prototype projection head, a centred-and-sharpened teacher / softer
//! student cross-entropy loss, an EMA teacher update, a centering buffer, and
//! the iBOT masked-patch term.
pub use ;