Added the ability to enable borders for the bar. (#428)

* Added the ability to configure a border for the bar.

* Added the right color for configs

themes/rose_pine_vivid.json

@@ -341,5 +341,6 @@
   "theme.bar.menus.menu.network.switch.puck": "#26233a",
   "theme.bar.menus.menu.network.switch.disabled": "#1f1d2e",
   "theme.bar.menus.menu.network.switch.enabled": "#c4a7e7",
-  "theme.bar.buttons.systray.customIcon": "#e0def4"
+  "theme.bar.buttons.systray.customIcon": "#e0def4",
+  "theme.bar.border.color": "#c4a7e7"
 }