docs(materialized_artifact_build): drop ENV_PREFIX doc comment

Author: claude

crates/materialized_artifact_build/src/lib.rs

@@ -1,8 +1,5 @@
 use std::{fs, path::Path};
 
-/// Namespace prefix for the env vars set by [`register`] and consumed by
-/// `materialized_artifact`'s `artifact!` macro. Exported so both crates agree
-/// on the same prefix.
 pub const ENV_PREFIX: &str = "MATERIALIZED_ARTIFACT_";
 
 /// Publish an artifact at `path` so `materialized_artifact`'s `artifact!($name)`