Add profile conditions, scene presets, MQTT integration, and Scenes tab

Feature 1 — Profile Conditions: time-of-day, system idle (Win32
GetLastInputInfo), and display state (GUID_CONSOLE_DISPLAY_STATE)
condition types for automatic profile activation.

Feature 2 — Scene Presets: snapshot/restore system that captures target
running states, device brightness, and profile enables. Server-side
capture with 5-step activation order. Dedicated Scenes tab with
CardSection-based card grid, command palette integration, and dashboard
quick-activate section.

Feature 3 — MQTT Integration: MQTTService singleton with aiomqtt,
MQTTLEDClient device provider for pixel output, MQTT profile condition
type with topic/payload matching, and frontend support for MQTT device
type and condition editor.

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

server/src/wled_controller/api/__init__.py

@@ -15,6 +15,7 @@ from .routes.audio_sources import router as audio_sources_router
 from .routes.audio_templates import router as audio_templates_router
 from .routes.value_sources import router as value_sources_router
 from .routes.profiles import router as profiles_router
+from .routes.scene_presets import router as scene_presets_router
 
 router = APIRouter()
 router.include_router(system_router)
@@ -30,5 +31,6 @@ router.include_router(audio_templates_router)
 router.include_router(value_sources_router)
 router.include_router(picture_targets_router)
 router.include_router(profiles_router)
+router.include_router(scene_presets_router)
 
 __all__ = ["router"]