Query functions now return plain data objects. Two renderers
(render_human, render_json) handle output formatting. A single
run_query dispatcher routes to the right data function by file
type and query name, then main() calls the appropriate renderer
based on --format. Eliminates duplicated *_json variants and
the OUTPUT_FORMAT global.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>