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Per the consolidation onto El: 'crates' is the Rust word, 'vessel' is El's (per spec/language.md §15). The directory rename is the structural marker that this slot holds an El buildable unit, even if its current contents are still Rust pending port. Mechanical: git mv crates vessels, sed workspace members and any path dependencies, update CI workflow paths, update README references. Cross-repo path dependencies (`../foo/crates/bar`) updated workspace- wide so cargo metadata still resolves where the Rust still builds.