"""Reusable pieces of the OSM → Blender/Cesium asset pipeline.

The package is split by dependency, not by feature:

- `osm`  and `geom` are pure Python.  They import no `bpy` and can be run and
  tested with a plain interpreter (`python3 -m unittest discover blender/tests`).
- everything else may touch `bpy` and only runs inside Blender.

Keeping that line sharp is what makes the geometry testable at all; before the
split it was interleaved with scene construction and could only be exercised by
rendering a whole area.
"""