Damage movespeed (#5244)

Content.Shared/Damage/Components/SlowOnDamageComponent.cs

@@ -0,0 +1,22 @@
+using System.Collections.Generic;
+using Content.Shared.FixedPoint;
+using Robust.Shared.GameObjects;
+using Robust.Shared.GameStates;
+using Robust.Shared.Serialization.Manager.Attributes;
+
+namespace Content.Shared.Damage.Components
+{
+    // TODO It'd be nice if this could be a destructible threshold, but on the other hand,
+    // that doesn't really work with events at all, and
+    [RegisterComponent, NetworkedComponent]
+    public class SlowOnDamageComponent : Component
+    {
+        public override string Name => "SlowOnDamage";
+
+        /// <summary>
+        ///     Damage -> movespeed dictionary. This is -damage-, not -health-.
+        /// </summary>
+        [DataField("speedModifierThresholds", required: true)]
+        public readonly Dictionary<FixedPoint2, float> SpeedModifierThresholds = default!;
+    }
+}