Reject bad geo input at write time (code 16572)
v0.3.0a42 hardens geo write-side validation: invalid coordinates and malformed shape definitions are now rejected at index-write time with the same error code real mongod uses (code: 16572), instead of being silently accepted and only failing on read. The check covers Polygon ring closure, longitude/latitude ranges, and malformed GeoJSON.
The marketing site also picked up its drop-in code-comparison: the home page now shows two side-by-side snippets (Normal MongoDB vs Embedded SecantusDB) where the application code is byte-identical and only the setup line differs.