SkyGround REBORN

# SkyGround REBORN 4.9

## ⚠️ Read first
- **NeoForge 21.1.250** is now required.
- **New world generation:** Terralith replaced by **Oh The Biomes We've Gone** + **Oh The Trees You'll Grow**. Recommended for new worlds. Terralith is still included but **disabled** – for existing Terralith worlds, enable Terralith and disable BWG + OTYG.
- **RAM:** 8 GB minimum, 10 GB recommended.

## Added
- Oh The Biomes We've Gone 2.6.0, Oh The Trees You'll Grow 5.3.2

## Removed
- DimThread (wasted a full CPU core idling, crash risk with Sable/Aeronautics)
- Create: Oritech Compat (1.20.1 file, broken recipes)
- X-Ray resource pack

## Updated
- JEI, Petrolpark, Create: Crafts & Additions, Create Enchantment Industry, Industrial Foregoing, Titanium, Electrodynamics, Polymorph, Simple Voice Chat, Vista, Euphoria Patcher
- Iris re-enabled (shaders off by default)

## Performance
- ServerCore auto-tuning enabled – mob cap and chunk ticking scale down under load, far fewer stutters while exploring/flying
- Distant Horizons tuned (128 radius, medium quality, throttled threads)
- No more bat spawns
- Low-end defaults for fresh installs (render 8 / sim 6) – existing settings untouched
- Cleaned JVM flags, faster startup