Add ResolveInFrameA type

Author: AbdulrhmnGhanem

src/Mechanical/MultiBody2D/types.jl

@@ -0,0 +1,14 @@
+
+@enum ResolveInFrameA begin
+    world
+    frame_a
+    frame_resolve
+end
+
+Base.@doc """
+    Enumeration to define the frame in which an absolute vector is resolved (world, frame_a, frame_resolve)
+    Values:
+        - `world`: Resolve in world frame
+        - `frame_a`: Resolve in frame_a"
+        - `frame_resolve`: Resolve in frame_resolve (frame_resolve must be connected)
+""" ResolveInFrameA