Chrome headless print-to-pdf: fix overflow via @page margins, not content

Rendering an HTML memo to a fixed page count with Chrome headless --print-to-pdf, a single orphan row spilling to an extra page resisted content trims (tighter table padding, smaller section margins, smaller footer margins all produced a byte-identical PDF and no page-count change). Shrinking @page margin from 13mm/11mm to 11mm/9mm fixed it instantly: page-box geometry dominates small in-flow adjustments. Verify with a real render loop, not by eye - mdls -name kMDItemNumberOfPages caches stale values, so trust the pages count from a Quartz CGPDFDocumentGetNumberOfPages script that also rasterizes each page to PNG so you can see which page is the orphan. Rasterizing revealed the overflow was only the footer block, not the table, which redirected the fix entirely.