fix(spawning): coalesce and gate WorldSpawnManager environment recalcs

[Xytronix]

Summary

WorldSpawnManager.onEnvironmentChanged() schedules a environment recalc for every world on every call, these are about 40000 unnecessary recalcs on a 29 world server with each using 40-70ms of tick time.

O(worlds² × roles) is suboptimal, this Mixin only queues one recalc per world at a time.

Related issues

2026/05/28 03:47:15   WARN]         [World|Arena4] Task took 62ms 334us 470ns ns: com.hypixel.hytale.server.spawning.world.manager.WorldSpawnManager$$Lambda/0x0000000043f6cc00@1c1a50b9

Type of change

• Bug fix (non-breaking)
• New feature (non-breaking)
• Breaking change (requires documentation/migration)
• Chore / refactor
• Documentation only

Implementation details

• MixinWorldSpawnManager skip worlds where WorldConfig.isSpawningNPC() is false and patches absurd recalc logic of O(worlds² × roles) to only do one recalc per world

Checklist

• Code compiles successfully
• Pull request does not contain unrelated changes
• Changes follow this project's code style (Use spotlessApply when necessary)
• Changes are tested or will be tested after submission