Adds brightness (0.0-1.0) to KeyColorsSettings, applies scaling in the
KC processing pipeline after smoothing, exposes a slider on the WebUI
target card, and creates a HA number entity for KC target brightness.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add a Number platform to the HAOS integration so each LED target
with a brightness-capable device gets a 0-255 slider in Home
Assistant. Coordinator now fetches device list and brightness on
each poll cycle. Also enable chart animation in perf-charts.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
