Previously, when a slide contained bullet points before and after a
table, content would be split across multiple slides or use a two-column
layout that didn't preserve the source order.
This change:
1. Modified `splitBlocks'` in Presentation.hs to continue accumulating
content after tables instead of immediately splitting to a new slide.
2. When a slide has a table with surrounding text, use ContentSlide
(single column) instead of ContentWithCaptionSlide (two columns)
to preserve content order.
3. Added vertical stacking in Output.hs (shapesToElementsStacked) to
properly position multiple shapes (tables + text) within a content
area. Space is allocated proportionally based on content size
(paragraphs and table rows).
Closes#11433.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Co-authored-by: Chris Callison-Burch <ccb+github@upenn.edu>
