(extensions.lightmaps) Select Faces lump for Source Engine `lightmap_faces`

[snake-biscuits]

I'd like to compare Faces to FacesHDR
Specifically how the lightmaps compare

Currently lightmaps.source.face_lightmaps generates a LightmapCollection w/ both LDR & HDR
I'd like to split this into face_lightmaps & face_lightmaps_hdr
This could handle a pair of lumps

• FACES & LIGHTING
• FACES_HDR & LIGHTING_HDR

Would probably need a wrapper that selects one or the other
Since some maps only have LDR or HDR, tho plenty have both.

OriginalFaces could be wierd, which LIGHTING lump do they use?

There's also the per-face lightmap texel to consider
(encode in vertex.colour when remapping uv1?)

[snake-biscuits]

We should have a time of day picker for troika.vampire maps too
Could make a LightmapCollection for each then merge them

Maybe do the substitution trick to make multiple textures & explore the lightmap in blender

TODO: add a link to that script here