Tellus 1.21.1 Local Origin Test Build (with Simplified Chinese)

Test build for Minecraft 1.21.1.

This build adds an optional world-creation UI toggle:

Use selected spawn as local origin

When enabled, the location selected in the Tellus map screen is generated near Minecraft X=0, Z=0 instead of very large absolute coordinates. Terrain, biome, water, and OSM-related sampling were adjusted to account for the local coordinate offset.

This was tested with Zhangjiajie as the selected spawn location. The world generated near the origin, and Create Aeronautics / Sable physics contraptions worked normally.

Also includes a Simplified Chinese localization based on en_us.json.

This is an unofficial test build.