Fix empty bbox because of empty shapely_annotation.multipolygon

[vinnik-dmitry07]

Basically, the idea of this "if" section is to filter things like LineString from geometry.geoms but geometry.geoms can contain not only Polygon but MultiPolygon as well. Might be related to #1094, #1118, #1138.

[Copilot]

Pull Request Overview

This PR addresses an issue where an empty bounding box is produced due to handling of empty MultiPolygon annotations.

• Refactors the polygon filtering logic to accommodate both Polygon and MultiPolygon types found in geometry.geoms.
• Aims to prevent returning invalid or nested geometries when the collection contains MultiPolygon objects.

[Copilot]

Returning 'geom.geoms' here may result in a nested list when constructing a MultiPolygon, as MultiPolygon expects a flat list of Polygon objects. Consider flattening the list by extending the collection of polygons for MultiPolygon objects.

Suggested change

	polygons = [
	geom.geoms if isinstance(geom, MultiPolygon) else geom
	for geom in geometry.geoms if isinstance(geom, (Polygon, MultiPolygon))
	]
	polygons = []
	for geom in geometry.geoms:
	if isinstance(geom, Polygon):
	polygons.append(geom)
	elif isinstance(geom, MultiPolygon):
	polygons.extend(geom.geoms)