out-of-bounds memory access in SmokeLine

Screenshot: <img width="625" height="480" alt="Image" src="https://github.com/user-attachments/assets/38f7d9fb-b865-4167-bcdc-de83f86efb20" /> Location of memory access https://github.com/dethrace-labs/dethrace/blob/55de27d2a962f12fb61df4c280a6bdc9f498ded6/src/DETHRACE/common/spark.c#L1009 Stack trace: ``` __pthread_kill_implementation 0x00007ffff758c3cc SmokeLine spark.c:1009 SmokeCircle spark.c:1189 SmokeCircle3D spark.c:1306 RenderSmoke spark.c:1485 RenderAFrame graphics.c:2042 MainGameLoop mainloop.c:679 DoRace mainloop.c:811 DoGame structur.c:613 DoProgram structur.c:723 GameMain main.c:141 original_main allsys.c:902 main main.c:61 ```