Bumps the multi-page badge from text-xs (12px) / px-1.5 py-0.5 to
text-sm (14px) / px-2 py-1. Meets senior-legibility on a 320px phone
without crowding the 120-wide tile — the badge stays tucked in the
top-right corner.
Refs #305
Fixes @leonievoss senior-accessibility concern from PR review
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Reads thumbnailAspect from the backend and swaps between a 120×168
portrait tile and a 168×120 landscape tile so postcards and photos
don't get cropped into a portrait frame. Shows a page-count badge
top-right for multi-page PDFs, and a pulsing skeleton while the
async thumbnail job hasn't run yet. URL assembly goes through the
existing thumbnailUrl helper so cache-busting stays consistent
with DocumentThumbnail.
Refs #305
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
