SHIPPED IMPOSTOR ATLASES
========================
Pre-baked octahedral impostor atlases packaged with the mod, so players don't pay the
64-view runtime bake on first zoom into a biome (which would hitch on weaker GPUs than
the dev machine). Filenames MUST match the writable user-cache convention exactly:

    imp_<ImpVer>_<species>.png        e.g. imp_v2_tree_oak.png

The baker (ImpostorBaker.ReadOnlyCachePath, set in GlobeScatter.Pump) checks this folder
FIRST; on a hit it loads and NEVER writes back. Miss -> falls through to the writable
user cache (%APPDATA%/Godot/app_userdata/Ascent of Ashes/ashworldmap_impostors/), then a
fresh bake. A future ImpVer bump changes the filename, so stale shipped atlases are ignored
automatically (same as the user cache).

POPULATE AFTER EYEBALL (do NOT ship un-verified atlases):
  1. Open the map, zoom each biome so every baked species bakes into the user cache.
     Verify orientation/read of skull_desert / vehicle_wreck / scrap_chunk and the
     acacia/snowfir/rock_mesa/rock_snow/ice_shard/deadbush_desert batch.
  2. Copy the VERIFIED imp_v2_*.png from the user cache dir into this folder.
  3. Release rebuild + RE-SIGN the mod (adding files here changes the signed payload).

This folder is intentionally empty of atlases until the eyeball pass approves them.
