Branch script methods need regression tests

[snake-biscuits]

We need more tests to ensure stability.
#73 is going to lead to a lot of refactors & the variable names in methods need to stay up to date.

With #16, we'll have plenty of sample data
If the maps don't change, we can check for determinism

We might have to develop special test maps for some methods
A small test zoo to isolate & show of engine features would be cool (like Source SDK mapsrc/)

Good tests double as documentation, showing how to use features

Methods

• bspx
  • face_normals
• id_software.quake
  • face_mesh
  • leaves_of_node
  • lightmap_of_face
  • model
  • parse_vis
• id_software.quake2
  • face_mesh
• infinity_ward.call_of_duty1_demo
  • brush
  • model
  • patch_collision_mesh
  • portal_file
  • triangle_soup_mesh
• infinity_ward.modern_warfare
  • collision_part_mesh
  • layered_triangle_soup_mesh
  • simple_triangle_soup_mesh
• ion_storm.daikatana
  • plane_faces
• respawn.apex_legends
  • lit_vertex
  • mesh
  • shadow_mesh
  • texture_data_surface_name
  • unlit_vertex
  • water_body_model
• respawn.titanfall
  • brush
  • lit_vertex
  • mesh
  • model
  • occlusion_mesh
  • portals_as_prt
  • search_all_entities
  • shadow_mesh
  • tricoll_model
  • unlit_vertex
• shared
  • worldspawn_volume
• valve.source
  • displacement_mesh
  • face_mesh
  • model
  • textures_of_brush