fix: derive crop box from coordinate extent in `save_elements` (#4371)

`save_elements` assumed `points[0]` and `points[2]` were always the
top-left and bottom-right corners. For elements whose coordinates carry
(or were converted from) a y-up orientation, that ordering inverts the
PIL crop box and raises `ValueError: Coordinate 'lower' is less than
'upper'`. The error was silently swallowed, so the figure/table image
was dropped.

The crop box is now computed from the min/max of all coordinate points,
so it's always valid regardless of point ordering.

**Changes**
- `pdf_image_utils.save_elements`: use `min/max` over all points instead
of fixed corner indices
- Added a regression test for inverted/rotated coordinate ordering
- CHANGELOG + version bump to `0.22.35`

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---
## Summary by cubic
Fix image cropping in `pdf_image_utils.save_elements` by deriving the
crop box from the coordinate extent. This prevents the PIL "Coordinate
'lower' is less than 'upper'" error and stops figure/table images from
being dropped.

- **Bug Fixes**
- Compute the crop box with min/max over all points instead of assuming
fixed corners.
  - Add a regression test for inverted/rotated coordinate ordering.

<sup>Written for commit 0ea49ae7a0c0102e938994a808ad243c6d281a4d.
Summary will update on new commits.</sup>

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