Share the enclosing-assembly walk as AssemblyTreeNode.FindEnclosing

The "walk up to the enclosing AssemblyTreeNode" helper was byte-identical
in the open-terminal and open-containing-folder commands. Lift it to a
static on AssemblyTreeNode and route both through it.

Assisted-by: Claude:claude-opus-4-8:Claude Code

ILSpy/Commands/OpenCommandLineHereContextMenuEntry.cs

@@ -58,7 +58,7 @@ namespace ILSpy.Commands
 			var dirs = new List<string>(nodes.Length);
 			foreach (var node in nodes)
 			{
-				var assembly = FindEnclosingAssemblyNode(node);
+				var assembly = AssemblyTreeNode.FindEnclosing(node);
 				if (assembly is null)
 					return Array.Empty<string>();
 				var dir = Path.GetDirectoryName(assembly.LoadedAssembly.FileName);
@@ -69,16 +69,6 @@ namespace ILSpy.Commands
 			return dirs;
 		}
 
-		static AssemblyTreeNode? FindEnclosingAssemblyNode(SharpTreeNode? node)
-		{
-			while (node != null)
-			{
-				if (node is AssemblyTreeNode a)
-					return a;
-				node = node.Parent;
-			}
-			return null;
-		}
 
 		static void OpenTerminalAt(string directory)
 		{

ILSpy/Commands/OpenContainingFolderContextMenuEntry.cs

@@ -60,7 +60,7 @@ namespace ILSpy.Commands
 			var paths = new List<string>(nodes.Length);
 			foreach (var node in nodes)
 			{
-				var assembly = FindEnclosingAssemblyNode(node);
+				var assembly = AssemblyTreeNode.FindEnclosing(node);
 				if (assembly is null)
 					return System.Array.Empty<string>();
 				var path = assembly.LoadedAssembly.FileName;
@@ -71,16 +71,6 @@ namespace ILSpy.Commands
 			return paths;
 		}
 
-		static AssemblyTreeNode? FindEnclosingAssemblyNode(SharpTreeNode? node)
-		{
-			while (node != null)
-			{
-				if (node is AssemblyTreeNode a)
-					return a;
-				node = node.Parent;
-			}
-			return null;
-		}
 
 	}
 }

ILSpy/TreeNodes/AssemblyTreeNode.cs

@@ -75,6 +75,21 @@ namespace ILSpy.TreeNodes
 		{
 		}
 
+		/// <summary>
+		/// Walks up from <paramref name="node"/> (inclusive) to the nearest enclosing assembly node,
+		/// or null when the node sits outside any assembly.
+		/// </summary>
+		public static AssemblyTreeNode? FindEnclosing(SharpTreeNode? node)
+		{
+			while (node != null)
+			{
+				if (node is AssemblyTreeNode a)
+					return a;
+				node = node.Parent;
+			}
+			return null;
+		}
+
 		// Drag-drop (handled generically by SharpTreeView, which delegates to these). The drag
 		// payload is the assemblies' file paths so a reorder and an external file drop unify through
 		// AssemblyListTreeNode.Drop -> OpenAssembly (which dedupes) + Move.