The raycaster's door geometry now takes the live `doors[]` state instead of a boolean flag, so partially-open door cells let render rays pass through the already-slid portion to show what's genuinely beyond, rather than painting a flat "socket" fill. `intersectDoorMidplane` returns a slide-shifted `textureX` so the door texture visibly translates into the wall as it opens.
`WolfensteinView` samples the new `wolfenstein-doors` sheet the same way it does walls (source-texel column, vertical crop, multiply shading), falling back to the flat tan placeholder. Added the doors.png/.psd assets and a `sheets.doors` entry in the art manifest. Updated sprites.md to document the new sheet, the see-through behavior, and that this stays render-only (gameplay raycasts are unaffected).
