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/soviet-02b/map.ftl

@@ -0,0 +1,5 @@
+## rules.yaml
+briefing = 
+    Tomorrow, the attack on Germany begins, but today, we must protect our facility from Allied attacks.
+    
+    Keep the Command Center intact at all costs, and destroy any Allied fortifications you might find.