NEW ERA 1.87.4 — OFFICIAL VOID CENTURY COMPATIBILITY

Only New Era is updated. Use the original official Void Century 4.9.6 JAR.
The startup compatibility mixin is shipped and registered inside New Era. Its
plugin checks the exact upstream constructor pattern before enabling it. The
adapter is scoped to that constructor's explicit rejection check and retains
normal ModList discovery everywhere else. The demoniclegends mod ID, registry
names, assets and existing world identifiers are retained.

New Era 1.87.3's shared melee/precise-aim integration remains in place. The
official dependency's duplicate-mob integration sees New Era normally. With no
Void Century installed, the optional startup integration does not apply.

Build with Java 17, Forge 1.20.1 and the same dependency classpath as 1.87.3.
Compile src into work/classes, run package_release.py, then prepare_runtime.py
to generate isolated real Forge coexistence tests. The tests are not included
as production classes. Official dependency checksum is checked before and after
tests; no patched Void Century JAR is used in the test mod directory.
