fix(contain): remove destroyed detached occupants

[mreza0100]

Summary

• remove destroyed occupants before restoring a temporarily detached containment list
• mirror the fix in Generals and Zero Hour
• keep RETAIL_COMPATIBLE_CRC behavior unchanged

Root cause

OpenContain::processDamageToContained temporarily swaps m_containList out to avoid iterator invalidation. A nested destroyObject call cannot deregister a rider while that list is detached. If the rider is marked destroyed without becoming effectively dead, the old code restores it; deferred deletion then leaves a dangling pointer. A later container eviction can call TransportContain::onRemoving on the destructed object and crash in Object::onDisabledEdge because m_behaviors is null.

The fix excludes both effectively-dead and explicitly destroyed occupants before restoring the detached list. The normal live-occupant path is unchanged.

Validation

• macOS ARM64 Zero Hour target z_generals builds successfully
• macOS ARM64 Generals target g_generals builds successfully
• git diff --check passes
• retail-compatible CRC branch is unchanged

AI assistance

The crash report and engine lifecycle were analyzed with AI assistance. The final logic change was manually scoped to the identified list-detachment invariant and verified against both game variants and full native builds.

[mreza0100]

Thanks for the review! Updated both comment blocks (Generals/ and GeneralsMD/ OpenContain.cpp) to the GeneralsX @bugfix convention per CONTRIBUTING.md. Pushed in dba6867 — done.