A high-performance, zero-dependency Rust library for streaming conversion
between WKT/EWKT and WKB/EWKB geometry formats used in GIS systems (PostGIS,
GDAL, etc.).

Exposes both a Rust API and Python bindings (via PyO3/maturin).

Features:
- All 7 OGC geometry types: Point, LineString, Polygon, MultiPoint,
  MultiLineString, MultiPolygon, GeometryCollection
- All coordinate dimensions: XY, XYZ, M, ZM
- Both EWKB (PostGIS flag-bit encoding) and ISO WKB (type+1000 offset encoding)
  as input
- SRID preservation (EWKT <-> EWKB); option to split SRID from geometry
- Big-endian and little-endian WKB input; little-endian EWKB output for full
  conversions, with simple header rewrites preserving input byte order
- EMPTY geometry support
- Per-member EMPTY support inside MULTI* geometries
- Hex WKB convenience helpers
- Memory-safe handling for malformed input: structurally invalid input returns
  descriptive errors, while trusted-valid fast paths may pass through malformed
  geometry bodies as invalid output bytes/text.
