v1.4.0 - waycentral

Add GPU monitoring (-s GPU [N])

- Usage (averaged over 1 s), VRAM, temperature, power, core/memory
  clock and fan for every card in /sys/class/drm
- AMD/Intel/nouveau through sysfs and hwmon, NVIDIA through NVML loaded
  at runtime (no hard dependency), names from hwdata's pci.ids
- New wc_gpu_list / wc_gpu_json library API
- Bump version to 1.4.0

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>