executePostProcessing() only set inlineMode=true in the FSR2 path.
The FXAA and FSR1 paths both start INLINE render passes but returned
false, causing endFrame() to record ImGui into a secondary command
buffer and execute it inside the INLINE pass — validation errors and
UI disappearing on AMD RADV when FSR1+MSAA are both enabled.
CharacterRenderer::destroyModelGPU now defers vertex/index buffer
destruction when replacing models mid-stream, preventing use-after-free
on AMD RADV. FXAA descriptor sets are now per-frame to eliminate
write-read races between in-flight command buffers. Water reflection
descriptor update narrowed to current frame only.