Add audio sources as first-class entities, add mapped CSS type, simplify target editor for mapped sources

- Audio sources moved to separate tab with dedicated CRUD API, store, and editor modal
- New "mapped" color strip source type: assigns different CSS sources to distinct LED sub-ranges (zones)
- Mapped stream runtime with per-zone sub-streams, auto-sizing, hot-update support
- Target editor auto-collapses segments UI when mapped CSS is selected
- Delete protection for CSS sources referenced by mapped zones
- Compact header/footer layout

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

server/src/wled_controller/main.py

@@ -23,6 +23,7 @@ from wled_controller.storage.pattern_template_store import PatternTemplateStore
 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.profile_store import ProfileStore
 from wled_controller.core.profiles.profile_engine import ProfileEngine
 from wled_controller.utils import setup_logging, get_logger
@@ -42,8 +43,12 @@ picture_source_store = PictureSourceStore(config.storage.picture_sources_file)
 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)
 profile_store = ProfileStore(config.storage.profiles_file)
 
+# Migrate embedded audio config from CSS entities to audio sources
+audio_source_store.migrate_from_css(color_strip_store)
+
 processor_manager = ProcessorManager(
     picture_source_store=picture_source_store,
     capture_template_store=template_store,
@@ -51,6 +56,7 @@ processor_manager = ProcessorManager(
     pattern_template_store=pattern_template_store,
     device_store=device_store,
     color_strip_store=color_strip_store,
+    audio_source_store=audio_source_store,
 )
 
 
@@ -94,6 +100,7 @@ async def lifespan(app: FastAPI):
         picture_source_store=picture_source_store,
         picture_target_store=picture_target_store,
         color_strip_store=color_strip_store,
+        audio_source_store=audio_source_store,
         profile_store=profile_store,
         profile_engine=profile_engine,
     )