- stop_jean(): stops Jean service to free VRAM before Ollama use - start_jean(): starts Jean service when switching back from Ollama - unload_ollama(): forces Ollama to unload models before Jean use - ensure_vram_for_backend(): orchestrates VRAM switching - Tracks active backend state to avoid unnecessary switches - Configurable timeouts via environment variables - Prevents VRAM contention between Jean and Ollama