Add value sources for dynamic brightness control on LED targets

Introduces a new Value Source entity that produces a scalar float (0.0-1.0)
for dynamic brightness modulation. Three subtypes: Static (constant),
Animated (sine/triangle/square/sawtooth waveform), and Audio-reactive
(RMS/peak/beat from mono audio source). Value sources can be optionally
attached to LED targets to control brightness each frame.

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

server/src/wled_controller/main.py

@@ -24,6 +24,7 @@ from wled_controller.storage.picture_source_store import PictureSourceStore
 from wled_controller.storage.picture_target_store import PictureTargetStore
 from wled_controller.storage.color_strip_store import ColorStripStore
 from wled_controller.storage.audio_source_store import AudioSourceStore
+from wled_controller.storage.value_source_store import ValueSourceStore
 from wled_controller.storage.profile_store import ProfileStore
 from wled_controller.core.profiles.profile_engine import ProfileEngine
 from wled_controller.utils import setup_logging, get_logger
@@ -44,6 +45,7 @@ picture_target_store = PictureTargetStore(config.storage.picture_targets_file)
 pattern_template_store = PatternTemplateStore(config.storage.pattern_templates_file)
 color_strip_store = ColorStripStore(config.storage.color_strip_sources_file)
 audio_source_store = AudioSourceStore(config.storage.audio_sources_file)
+value_source_store = ValueSourceStore(config.storage.value_sources_file)
 profile_store = ProfileStore(config.storage.profiles_file)
 
 # Migrate embedded audio config from CSS entities to audio sources
@@ -57,6 +59,7 @@ processor_manager = ProcessorManager(
     device_store=device_store,
     color_strip_store=color_strip_store,
     audio_source_store=audio_source_store,
+    value_source_store=value_source_store,
 )
 
 
@@ -101,6 +104,7 @@ async def lifespan(app: FastAPI):
         picture_target_store=picture_target_store,
         color_strip_store=color_strip_store,
         audio_source_store=audio_source_store,
+        value_source_store=value_source_store,
         profile_store=profile_store,
         profile_engine=profile_engine,
     )