Add variant exported map needle for non-fullscreen window

This is a change in the image viewer app, or maybe fallout from
the menu_launch_type change, not sure. Anyhow, it's not really
a problem if the image viewer opens in a small window rather than
maximized, so let's just have a needle for it.

Signed-off-by: Adam Williamson <awilliam@redhat.com>

needles/gnome/apps/maps/maps_exported_map-smallwindow-20250426.json

@@ -0,0 +1,15 @@
+{
+  "area": [
+    {
+      "width": 141,
+      "height": 102,
+      "type": "match",
+      "ypos": 372,
+      "xpos": 446
+    }
+  ],
+  "properties": [],
+  "tags": [
+    "maps_exported_map"
+  ]
+}