oci: Re-export composefs crate

This is a followup to the commit which re-exports via cfsctl;
it's cleaner to make this transient here too.

Assisted-by: OpenCode (Claude Opus)
Signed-off-by: Colin Walters <walters@verbum.org>

Author: cgwalters

crates/composefs-oci/src/lib.rs

@@ -17,6 +17,9 @@ pub mod oci_image;
 pub mod skopeo;
 pub mod tar;
 
+// Re-export the composefs crate for consumers who only need composefs-oci
+pub use composefs;
+
 use std::{collections::HashMap, sync::Arc};
 
 use anyhow::{bail, ensure, Context, Result};