Don't set the GC mode when running on CoreCLR Unity documents GarbageCollector's mode control as Mono and IL2CPP only, "Not supported for CoreCLR", so Rust.GC.SetMode skips setting it there. ENABLE_CORECLR isn't defined in Unity's Mono builds, so main's builds still set the mode as before. Cherry-picked unchanged from unity_6.7.0's changeset 170208 (eb09ee70f16, "Don't try to set GC mode when using CoreCLR"). (cherry picked from commit eb09ee70f161c948d69e4d988f59f96f73788520) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>