Mouse rotator system (#19267)

Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>

Content.Shared/MouseRotator/MouseRotatorComponent.cs

@@ -0,0 +1,43 @@
+using System.Numerics;
+using Robust.Shared.GameStates;
+using Robust.Shared.Serialization;
+
+namespace Content.Shared.MouseRotator;
+
+/// <summary>
+/// This component allows overriding an entities local rotation based on the client's mouse movement
+/// </summary>
+/// <see cref="SharedMouseRotatorSystem"/>
+[RegisterComponent, NetworkedComponent, AutoGenerateComponentState]
+public sealed partial class MouseRotatorComponent : Component
+{
+    /// <summary>
+    ///     How much the desired angle needs to change before a predictive event is sent
+    /// </summary>
+    [DataField]
+    [ViewVariables(VVAccess.ReadWrite)]
+    public Angle AngleTolerance = Angle.FromDegrees(5.0);
+
+    /// <summary>
+    ///     The angle that will be lerped to
+    /// </summary>
+    [AutoNetworkedField, DataField]
+    public Angle? GoalRotation;
+
+    /// <summary>
+    ///     Max degrees the entity can rotate per second
+    /// </summary>
+    [DataField]
+    [ViewVariables(VVAccess.ReadWrite)]
+    public double RotationSpeed = float.MaxValue;
+}
+
+/// <summary>
+///     Raised on an entity with <see cref="MouseRotatorComponent"/> as a predictive event on the client
+///     when mouse rotation changes
+/// </summary>
+[Serializable, NetSerializable]
+public sealed class RequestMouseRotatorRotationEvent : EntityEventArgs
+{
+    public Angle Rotation;
+}