Transform wobble position angle convention from IACT to astropy

We were using astropy's convention (0 deg is North and then increase counterclockwise) rather than the IACT convention (0 deg is West and then increase clockwise)

src/iact_estimator/plots/wobble_skymap.py

@@ -200,7 +200,10 @@ def star_label_with_magnitude(star: Star) -> str:
     for angle, offset, color in zip(wobble_angles, wobble_offsets, color_map.colors):
         color = matplotlib_colors.to_hex(color)
 
-        wobble_center = target_coordinates.directional_offset_by(angle, offset)
+        # Transform IACT convention to astropy
+        position_angle = (90 * u.deg - angle) % (360 * u.deg)
+
+        wobble_center = target_coordinates.directional_offset_by(position_angle, offset)
         wobble_ra = wobble_center.ra.to_value("hourangle")
         wobble_dec = wobble_center.dec.to_value("deg")
 
@@ -245,5 +248,3 @@ def star_label_with_magnitude(star: Star) -> str:
             f"{target_source.name}_skymap_with_wobbles.{config['wobble_skymap_plot_options']['export']['format']}",
             **config["wobble_skymap_plot_options"]["export"],
         )
-
-    # plt.show()