feat(physics): IRigidbody Intertia and Inverse Mass & Intertia fields added

Engine.Physics2D/Abstract/IRigidBody2D.cs

@@ -27,6 +27,21 @@ public interface IRigidBody2D : IBehaviour2D
     /// </summary>
     float Mass { get; set; }
 
+    /// <summary>
+    /// The inverse mass (1 / Mass) of the <see cref="IRigidBody2D"/>.
+    /// </summary>
+    float InverseMass { get; }
+
+    /// <summary>
+    /// The Invertia of the <see cref="IRigidBody2D"/>.
+    /// </summary>
+    float Inertia { get; }
+
+    /// <summary>
+    /// The inverse Invertia (1 / Invertia) of the <see cref="IRigidBody2D"/>.
+    /// </summary>
+    float InverseInertia { get; }
+
     /// <summary>
     /// The value indicating whether the <see cref="IRigidBody2D"/> is static/immovable.
     /// </summary>