feat: add BufferGeometryUtils for advanced geometry manipulation

- Implemented computeMikkTSpaceTangents for consistent tangent generation.
- Added mergeGeometries to combine multiple BufferGeometries.
- Introduced mergeAttributes for merging BufferAttributes.
- Created deepCloneAttribute for cloning BufferAttributes.
- Developed interleaveAttributes and deinterleaveAttribute for attribute management.
- Added estimateBytesUsed to calculate memory usage of geometries.
- Implemented mergeVertices to optimize vertex data.
- Created toTrianglesDrawMode for converting geometries to triangle mode.
- Added computeMorphedAttributes for handling morph targets in geometries.
- Implemented mergeGroups to consolidate geometry groups.
- Developed toCreasedNormals for generating smooth normals with crease angles.

klabava/vendor/three/LICENSE

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