Initial commit: OpenRA game engine

Fork from OpenRA/OpenRA with one-click launch script (start-ra.cmd)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

mods/ra/maps/allies-04/map.ftl

@@ -0,0 +1,17 @@
+dropdown-difficulty =
+    .label = Difficulty
+    .description = The difficulty of the mission
+
+options-difficulty =
+    .easy = Easy
+    .normal = Normal
+    .hard = Hard
+    .tough = Real tough guy
+
+## rules.yaml
+briefing = 
+    Soviet forces are trying to retake the pass you cleared for our convoys.
+    
+    Don't let this happen. Hold the pass and prevent the Soviets from taking this vital area.
+    
+    Destroy all Soviet units and buildings in this region.