Viz add colorbar

https://www.notion.so/qim-dtu/Add-colorbar-to-vizualisation-tools-a1b4cb67bd4a4de39a7ac40bf5d35fd5

qim3d/viz/explore.py

@@ -192,9 +192,15 @@ def slices(
             ax.axis("off")
 
     if cbar:
+        fig.tight_layout()
         norm = matplotlib.colors.Normalize(vmin=new_vmin, vmax=new_vmax, clip=True)
         mappable = matplotlib.cm.ScalarMappable(norm=norm, cmap=cmap)
-        fig.colorbar(mappable=mappable, ax=np.atleast_1d(axs[0])[-1], orientation='vertical')
+
+        # Figure coordinates of top-right axis
+        tr_pos = np.atleast_1d(axs[0])[-1].get_position()
+        # The width is divided by ncols to make it the same relative size to the images
+        cbar_ax = fig.add_axes([tr_pos.x1 + 0.05/ncols, tr_pos.y0, 0.05/ncols, tr_pos.height])
+        fig.colorbar(mappable=mappable, cax=cbar_ax, orientation='vertical')
 
     if show:
         plt.show()