Add OGWedge primitive with Three.js wrapper, scene APIs, and example

[aka-blackboots]

Motivation

• Add wedge to the existing primitive set so wedge geometry can be generated, projected, and consumed by the JS/Three integration like other shapes.
• Expose wedge in scene management and wasm bindings so it can be added to scenes and exported to 2D projections/PDFs.
• Provide a Three.js wrapper and a browser example to visualize the wedge from the wasm bindings.

Description

• Introduced a new kernel primitive OGWedge implemented in main/opengeometry/src/primitives/wedge.rs with center, width, height, depth, geometry generation, outline serialization and to_projected_scene2d support.
• Exported the primitive in main/opengeometry/src/lib.rs and wired scene APIs in main/opengeometry/src/scenegraph.rs including internal add_wedge_to_scene_internal and wasm-exposed addWedgeToScene / addWedgeToCurrentScene methods.
• Updated the PDF example main/opengeometry/examples/pdf_primitives_all.rs to create an OGWedge and include a projected wedge PDF export.
• Added Three.js integration: main/opengeometry-three/src/shapes/wedge.ts implements a Wedge wrapper using OGWedge, exported it in main/opengeometry-three/src/shapes/index.ts, and added a browser demo page at main/opengeometry-three/examples/wedge.html that loads wasm and renders the wedge.

Testing

• Ran formatting and build checks with cargo fmt -- --check, cargo check, and unit tests with cargo test, and all succeeded.
• Built wasm bindings and the Three package using npm run build-core and npm run build-three, and both builds completed successfully.

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Codex Task