Fix polyline tool calculation when dealing with 180 degrees angles.

src/bonsai/bonsai/tool/cad.py

@@ -102,6 +102,10 @@ class Cad:
         d1 = v1 - v2
         d2 = v3 - v2
 
+        # Rounding avoids problems when dealing with 180 degrees
+        d1 = Vector((round(c, 6) for c in d1))
+        d2 = Vector((round(c, 6) for c in d2))
+
         d1.normalize()
         d2.normalize()
 
@@ -123,12 +127,24 @@ class Cad:
         if new_angle is not None:
             rot_mat = Matrix.Rotation(new_angle, 3, axis)
             rot_vector = (d1 @ rot_mat) if parameter else (rot_mat @ d1)
+             
+            # 180 degrees special cases
+            if abs(round(a, 4)) == round(math.pi, 4) and (
+                rot_vector.x == 0.0 and rot_vector.y == 0.0 or
+                rot_vector.x == 0.0 and rot_vector.z == 0.0 or
+                rot_vector.y == 0.0 and rot_vector.z == 0.0
+                ):
+                rot_vector *= -1
             return rot_vector
         else:
             sign = -1 if parameter else 1
 
             if degrees:
                 a = math.degrees(a)
+                 
+                # 180 degrees special cases
+                if abs(round(a, 2)) == abs(180.00):
+                    return -180.0
                 return a * sign
             else:
                 return a