Package h3 provides a native Go implementation of the H3 geospatial indexing system. Public API matches github.com/uber/h3-go/v4 exactly. All lat/lng inputs and outputs are in DEGREES (the public API uses degrees). Internally, the faceijk package uses RADIANS. Package h3 - directed edge functions. Ported from the C H3 reference implementation (directedEdge.c).