Simplify scenes to capture only target state, add target selector

- Remove DeviceBrightnessSnapshot and AutomationSnapshot from scene data model
- Simplify capture_current_snapshot and apply_scene_state to targets only
- Remove device/automation dependencies from scene preset API routes
- Add target selector (combobox + add/remove) to scene capture modal
- Fix stale profiles reference bug in scene_preset_store recapture
- Update automation engine call sites for simplified scene functions
- Sync scene presets cache between automations and scene-presets modules

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

server/src/wled_controller/api/schemas/scene_presets.py

@@ -15,22 +15,13 @@ class TargetSnapshotSchema(BaseModel):
     auto_start: bool = False
 
 
-class DeviceBrightnessSnapshotSchema(BaseModel):
-    device_id: str
-    software_brightness: int = 255
-
-
-class AutomationSnapshotSchema(BaseModel):
-    automation_id: str
-    enabled: bool = True
-
-
 class ScenePresetCreate(BaseModel):
     """Create a scene preset by capturing current state."""
 
     name: str = Field(description="Preset name", min_length=1, max_length=100)
     description: str = Field(default="", max_length=500)
     color: str = Field(default="#4fc3f7", description="Card accent color")
+    target_ids: Optional[List[str]] = Field(None, description="Target IDs to capture (all if omitted)")
 
 
 class ScenePresetUpdate(BaseModel):
@@ -50,8 +41,6 @@ class ScenePresetResponse(BaseModel):
     description: str
     color: str
     targets: List[TargetSnapshotSchema]
-    devices: List[DeviceBrightnessSnapshotSchema]
-    automations: List[AutomationSnapshotSchema]
     order: int
     created_at: datetime
     updated_at: datetime