Function slug_derivation_help 

pub fn slug_derivation_help() -> String

--help text describing the title→slug pipeline. Shared by memstead create and memstead rename so an agent reading either command’s help can predict what slug a given title will produce (and therefore why the strict gate refuses titles outside the pipeline’s accepted character classes). The leading title-grammar rule is derived from the validator’s own memstead_base::TITLE_GRAMMAR_RULE at build time, not transcribed — the docs cannot drift from the accept set alone.