M2 destroyInstanceBones and WMO destroyGroupGPU freed descriptor sets
and buffers immediately during tile streaming, while in-flight command
buffers still referenced them — causing DEVICE_LOST on AMD RADV.
Now defers GPU resource destruction via deferAfterFrameFence in streaming
paths (removeInstance, removeInstances, unloadModel). Immediate
destruction preserved for shutdown/clear paths that vkDeviceWaitIdle
first.
Also: vkDeviceWaitIdle before WMO backfillNormalMaps descriptor rebinds,
and fillModeNonSolid added to required device features for wireframe
pipelines on AMD.
ac5c61203d