PPTX writer: bullet points before/after table split across multiple slides

[ccb]

When converting markdown to PPTX, bullet points that appear before and after a table on the same slide get split across multiple slides, or appear in incorrect order.

Minimal example:

## Slide Title

- Bullet before table
- Another bullet

| Col A | Col B |
|-------|-------|
| Val 1 | Val 2 |

- Bullet after table

Command:

pandoc input.md -o output.pptx

Expected behavior:
All content (bullets before table, table, bullets after table) should appear together on a single slide in the correct order.

Actual behavior:
The content gets split across multiple slides, with bullets appearing on separate slides from the table, or the ordering of content is incorrect.

Pandoc version:
3.8.3 (tested on macOS)

Note: I have submitted PR #11411 with a proposed fix for this issue.