GPU detection results were only applied at container creation time and
never persisted. If live detection failed transiently (Docker daemon
hiccup, runtime temporarily unavailable), Ollama would silently fall
back to CPU-only mode with no way to recover short of force-reinstall.
Now _detectGPUType() persists successful detections to the KV store
(gpu.type = 'nvidia' | 'amd') and uses the saved value as a fallback
when live detection returns nothing. This ensures GPU config survives
across container recreations regardless of transient detection failures.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>