fusion-wither

First public release.

Features
- Reworked vanilla Wither for Minecraft 1.20.1 (Forge 47.x), merging the Java fight loop with Bedrock Edition attacks
- Vanilla 1.20.1 awakening sequence preserved in full: hover, soul particles, charging boss bar, closing explosion and roar
- Phase 1: ranged kiting at 6.5-8.5 blocks, staggered three-head barrage on independent cooldowns, 1-2 Bedrock-style dashes
- Berserk below 50% HP: shorter shot intervals and straight-line charges
- Phase 2: straight-down entry fall, 4-tick pause, explosion transition; hovers 2-3 blocks above ground and deflects all projectiles
- Weighted behaviour pool (barrage / ground-slam) with a low-pressure idle window between cooldowns
- Death sequence with stretched model and pitch-falling wail, while loot, XP and kill credit stay vanilla
- 43 tuning values in config/fusion_wither-common.toml, applied with /reload
- /wboss debug command for phases, behaviours, cooldowns, armour and health

Requirements
- Minecraft 1.20.1, Forge 47.x, Java 17
- No extra dependencies; safe to add to an existing world