Move and rename damage effect to color flash effect (#18263)

* move damage effect to different package

* rename to ColorFlashEffect

* renaming some other things

Content.Shared/Effects/ColorFlashEffectComponent.cs

@@ -0,0 +1,11 @@
+namespace Content.Shared.Effects;
+
+/// <summary>
+/// Stores the original sprite color for flashing entity to be able to restore it later.
+/// </summary>
+[RegisterComponent]
+public sealed class ColorFlashEffectComponent : Component
+{
+    [ViewVariables]
+    public Color Color = Color.White;
+}