Add Daylight Cycle value source type

New value source that outputs brightness (0-1) based on the daylight
color LUT, computing BT.601 luminance from the simulated sky color.
Supports real-time wall-clock mode or configurable simulation speed.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/wled_controller/static/js/app.js

@@ -132,6 +132,7 @@ import {
 import {
     showValueSourceModal, closeValueSourceModal, saveValueSource,
     editValueSource, cloneValueSource, deleteValueSource, onValueSourceTypeChange,
+    onDaylightVSRealTimeChange,
     addSchedulePoint,
     testValueSource, closeTestValueSourceModal,
 } from './features/value-sources.js';
@@ -409,6 +410,7 @@ Object.assign(window, {
     cloneValueSource,
     deleteValueSource,
     onValueSourceTypeChange,
+    onDaylightVSRealTimeChange,
     addSchedulePoint,
     testValueSource,
     closeTestValueSourceModal,