solara_viz: Add borders around ContinuousSpace (#1988)

* solara_viz: Add grey background and borders

* solara_viz: Render axis

* solara_viz: Better dash

Use a 'loosely dashed' line for torus=True

See https://matplotlib.org/stable/gallery/lines_bars_and_markers/linestyles.html

* solara_viz: Remove background color

mesa/experimental/components/matplotlib.py

@@ -22,7 +22,6 @@ def SpaceMatplotlib(model, agent_portrayal, dependencies: Optional[list[any]] =
         _draw_continuous_space(space, space_ax, agent_portrayal)
     else:
         _draw_grid(space, space_ax, agent_portrayal)
-    space_ax.set_axis_off()
     solara.FigureMatplotlib(space_fig, format="png", dependencies=dependencies)
 
 
@@ -93,14 +92,23 @@ def portray(space):
             out["c"] = c
         return out
 
+    # Determine border style based on space.torus
+    border_style = 'solid' if not space.torus else (0, (5, 10))
+
+    # Set the border of the plot
+    for spine in space_ax.spines.values():
+        spine.set_linewidth(1.5)
+        spine.set_color('black')
+        spine.set_linestyle(border_style)
+
     width = space.x_max - space.x_min
     x_padding = width / 20
     height = space.y_max - space.y_min
     y_padding = height / 20
     space_ax.set_xlim(space.x_min - x_padding, space.x_max + x_padding)
     space_ax.set_ylim(space.y_min - y_padding, space.y_max + y_padding)
-    space_ax.scatter(**portray(space))
 
+    # Portray and scatter the agents in the space
     space_ax.scatter(**portray(space))