Add day_started signal and related functionality to event bus and systems

rust/src/consts.rs

@@ -10,5 +10,6 @@ pub const LIFT_VISUAL_HEIGHT: &str = "lift_visual_height";
 pub const CAMERA_TRAUMA: &str = "camera_trauma";
 pub const HAZARD_SPAWNED: &str = "hazard_spawned";
 pub const HAZARD_RESOLVED: &str = "hazard_resolved";
+pub const DAY_STARTED: &str = "day_started";
 
 pub const VIGNETTE_INTENSITY_PARAM: &str = "vignette_intensity";