Add Hanzhong gate scenario

data/campaign/campaign.json

@@ -198,6 +198,11 @@
       "id": "039_hanzhong_approach",
       "title": "Hanzhong Approach",
       "path": "res://data/scenarios/039_hanzhong_approach.json"
+    },
+    {
+      "id": "040_hanzhong_gate",
+      "title": "Hanzhong Gate",
+      "path": "res://data/scenarios/040_hanzhong_gate.json"
     }
   ]
 }