Add adaptive brightness value source with time-of-day and scene modes

New "adaptive" value source type that automatically adjusts brightness
based on external conditions. Two sub-modes: time-of-day (schedule-based
interpolation with midnight wrap) and scene brightness (frame luminance
analysis via numpy BT.601 subsampling with EMA smoothing).

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

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

@@ -112,6 +112,7 @@ import {
 import {
     showValueSourceModal, closeValueSourceModal, saveValueSource,
     editValueSource, deleteValueSource, onValueSourceTypeChange,
+    onAdaptiveModeChange, addSchedulePoint,
 } from './features/value-sources.js';
 
 // Layer 5: calibration
@@ -330,6 +331,8 @@ Object.assign(window, {
     editValueSource,
     deleteValueSource,
     onValueSourceTypeChange,
+    onAdaptiveModeChange,
+    addSchedulePoint,
 
     // calibration
     showCalibration,