port: SVG edge classification (#3668) onto wgpu [worklist #114-120]

Ports the 7-commit v0.8.0 SVG edge-classification feature (f0970b90b +
6 follow-ups) onto wgpu's heavily-diverged serializer. Reconstructed
block-by-block rather than merged, because both sides rewrote
SvgSerializer (v0.8.0 +419, wgpu +778) and git's conflict alignment was
misleading.

Key wgpu adaptations reasoned per block:
- IfcUtil::IfcBaseEntity* (pointer identity) -> express::Base (value),
  incl. as a std::map key in draw_hlr (express::Base has operator<);
  nullptr fallback -> express::Base{}
- boost::optional -> std::optional (css_class, dash_array)
- hlr_calc::result_type pair -> 3-tuple (adds per-edge class label)
- draw_hlr restructured with a group_by_product map: ONE path_object per
  product so multiple class buckets share a group and per-path classes
  survive Bonsai's merge (NOT naive per-item threading, which fragments
  groups -- caught during visual verification)
- settings wired into wgpu's apply_settings() (ctor-called), NOT the
  feature's added ready() call which wgpu already solved differently
- logger_.Warning -> logger().warning in write(geometry_data)

Verified end-to-end via IfcConvert on a curved-geometry stress scene
(Suzanne/Torus/Sphere/Cube/Cone/...): edges classify into outline/sharp/
crease/boundary/flush with correct per-product grouping and CSS styling.
Requires the model's storey to carry an Elevation and --svg-project to
trigger the HLR projection.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/ifcopenshell-python/ifcopenshell/geom/main.py

@@ -112,6 +112,12 @@ SETTING = Literal[
     "reorient-shells",
     "site-local-placement",
     "surface-colour",
+    "svg-emit-flush-edges",
+    "svg-render-crease-edges",
+    "svg-render-sharp-edges",
+    "svg-ridge-angle-min-degrees",
+    "svg-use-edge-classification",
+    "svg-valley-angle-min-degrees",
     "triangulation-type",
     "unify-shapes",
     "use-material-names",