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>

OpenRA.Mods.Common/Traits/Buildings/GivesBuildableArea.cs

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+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * This file is part of OpenRA, which is free software. It is made
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version. For more
+ * information, see COPYING.
+ */
+#endregion
+
+using System.Collections.Frozen;
+
+namespace OpenRA.Mods.Common.Traits
+{
+	[Desc("This actor allows placement of other actors with 'RequiresBuildableArea' trait around it.")]
+	public class GivesBuildableAreaInfo : ConditionalTraitInfo
+	{
+		[FieldLoader.Require]
+		[Desc("Types of buildable area this actor gives.")]
+		public readonly FrozenSet<string> AreaTypes = FrozenSet<string>.Empty;
+
+		public override object Create(ActorInitializer init) { return new GivesBuildableArea(this); }
+	}
+
+	public class GivesBuildableArea : ConditionalTrait<GivesBuildableAreaInfo>
+	{
+		public GivesBuildableArea(GivesBuildableAreaInfo info)
+			: base(info) { }
+
+		public FrozenSet<string> AreaTypes => !IsTraitDisabled ? Info.AreaTypes : FrozenSet<string>.Empty;
+	}
+}