MOAD-0005 (Thundering Herd / CWE-362): CLEAN

Searched blenkernel/ for cache patterns (get+null+compute+put without lock).
Blender's main data structures (ID caches, depsgraph) are single-threaded by
design. The render pipeline has explicit per-thread data (render tiles). No
concurrent cache get+compute+put without synchronization pattern found in
blenkernel or depsgraph. No Thundering Herd defect found.
