areev-cal-feature

Playbook for extending CAL (Context Assembly Language) in areev-cal — the ordered chain of files to touch, the OMS-conformance gate on new syntax, preserving the three-layer destructive-op block, and the Ok(Unsupported) result convention. Use before adding a CAL keyword, statement, WITH option, pipeline stage, or format clause, or editing lexer.rs / parser.rs / executor.rs.