Replace the four headline gauges (GPU temp, GPU load, CPU temp, memory) with
HistoryGraph trend tiles: each plots its session history with the current value,
window min/max, a dashed warn-threshold line, and a kind-colored line (temp band
/ usage / accent). QPainter-drawn, no new dependency. Seeing changes over time is
more useful than the live-only snapshot.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
jessey