feat(ole): render EMF/WMF OLE presentations

OLE2FRAME entities whose compound file carries a metafile presentation
(Excel/Word previews, scanned WMF pages) drew only their border frame —
the old decoder scanned the raw blob for a contiguous BMP, which the
CFB sector layout almost never provides. acadrust now extracts the
picture bytes tagged by kind; the new scene/model/gdi player rasterizes
EMF and WMF record streams on the CPU (pens/brushes, polygons, paths,
DIB blits, clipping, transforms) with text drawn through the existing
system-font glyph cache, and image_model feeds the result into the
raster pipeline. Rasters (BMP/PNG/JPEG/GIF, CF_DIB) decode as before
via the image crate.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/scene/model/mod.rs

@@ -1,7 +1,9 @@
 pub mod wire_model;
+pub mod gdi;
 pub mod hatch_model;
 pub mod hatch_patterns;
 pub mod image_model;
+pub mod ole_pres;
 pub mod mesh_model;
 pub mod solid_model;
 pub mod object;