fix(3d-synthezier): correct mirrored face winding in generated OBJ files

fix(3d-synthezier): correct mirrored face winding in generated OBJ files

The parser negates Z when writing vertices but emitted faces in their original order, so every generated OBJ had globally mirrored winding - building walls pointed inward and one-sided lighting/GI in consuming renderers produced uniform gray facades. Faces are now emitted reversed to compensate, and the transform stack tracks negative-scale (mirror) parity so mirrored instances flip winding back automatically.

Sixteen include files also had faces authored inward (dome, prisms, pipe, plate, solar, police parts, car, bus, hextower, roof slabs); these are flipped at source. Roof slabs had been authored downward and only rendered correctly by accident of the parser bug.

Component and material names are now English (maja->building, krs->storey, sein->wall, blk->window/hextower, nrk->prism, katus->roof, kuppel->dome, pol->police, muld->soil, kivi->stone and so on), and the scene language gained readable command aliases (origin, use, pick, pickmtl, ifeq, if) with all scene files and documentation converted. Both cities regenerated; AGENTS.org documents layout, build, language essentials and winding rules.