feat: add BufferGeometry to PostGIS POLYHEDRALSURFACE Z conversion utilities

[zamderax]

Summary

Add utilities for converting Three.js BufferGeometry to/from PostGIS POLYHEDRALSURFACE Z WKT format, enabling 3D geofence storage in spatial databases.

New Functions

Function	Description
bufferGeometryToWKT(geometry, options)	Convert BufferGeometry → PostGIS WKT
wktToBufferGeometry(wkt, options)	Parse WKT → BufferGeometry
isCoordsInPolyhedron(coords, geometry, origin)	Test if geo-coords are inside 3D volume
isPointInPolyhedron(point, geometry)	Test if 3D point is inside geometry
bufferGeometryToGeoTriangles(geometry, origin)	Convert to JSON-serializable GeoTriangle[]
geoTrianglesToBufferGeometry(triangles, origin)	Convert GeoTriangle[] → BufferGeometry
isPointOnSurface(point, geometry, tolerance)	Test if point is on surface

Use Case

Users can draw 3D volumes representing geofences in geographic coordinates (lat/lng/altitude), store them in PostGIS with geometry(POLYHEDRALSURFACEZ, 4326), and query point containment.

// Convert geometry to WKT for PostGIS storage
const wkt = bufferGeometryToWKT(geofence, { origin });
// INSERT INTO geofences (geom) VALUES (ST_GeomFromText(wkt, 4326))

// Test if a point is inside the geofence
const result = isCoordsInPolyhedron(testPoint, geofence, origin);
if (result.inside) {
  console.log('Point is inside geofence!');
}

Includes

• ✅ Comprehensive unit tests (39 tests)
• ✅ User-friendly error messages with context
• ✅ TypeDoc documentation with @throws and @example tags
• ✅ README documentation section
• ✅ Interactive Storybook demo

Test plan

• Run npm run vitest - all 39 tests pass
• Run npx tsc --noEmit - no type errors
• Run Storybook and verify Geofence demo works
• Test WKT output in PostGIS (optional)

🤖 Generated with Claude Code