Check text against a style guide

Check a text for compliance with caller-supplied style rules (house style, brand voice, editorial guidelines). Returns violations — each with the verbatim offending passage, its start/end offsets in the submitted text (null when the passage cannot be located), the violated rule name, a brief note and a compliant rewrite suggestion — plus a top-level compliant boolean. Only the listed rules are enforced; an empty violations list means the text complies. The text is checked as submitted (markup included), so offsets always index it directly. Provide exactly one of rules (inline) or ruleset (the name of a rule set saved via the API).