feat(gui): collapse single-child directory chains in resource tree (PR #2866)

jadx-gui/src/main/java/jadx/gui/treemodel/JResource.java

@@ -2,6 +2,7 @@ package jadx.gui.treemodel;
 
 import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
@@ -69,7 +70,7 @@ public class JResource extends JLoadableNode {
 	}
 
 	private final transient String name;
-	private final transient String shortName;
+	private transient String shortName;
 	private final transient JResType type;
 	private final transient ResourceFile resFile;
 
@@ -159,6 +160,50 @@ public class JResource extends JLoadableNode {
 		}
 	}
 
+	/**
+	 * Collapse single-child DIR chains into one node with a slash-joined display name (GitHub-style).
+	 */
+	public static void mergeMiddleDirs(JResource root) {
+		mergeChildren(root.subNodes);
+	}
+
+	public static void mergeMiddleDirs(List<JResource> roots) {
+		mergeChildren(roots);
+	}
+
+	private static void mergeChildren(List<JResource> children) {
+		for (int i = 0; i < children.size(); i++) {
+			JResource sub = children.get(i);
+			JResource replaced = mergeChain(sub, new ArrayList<>());
+			if (replaced != sub) {
+				children.set(i, replaced);
+			}
+			mergeChildren(replaced.subNodes);
+		}
+	}
+
+	private static JResource mergeChain(JResource node, List<JResource> merged) {
+		if (node.type == JResType.DIR) {
+			List<JResource> subs = node.subNodes;
+			if (subs.size() == 1 && subs.get(0).type == JResType.DIR) {
+				merged.add(node);
+				return mergeChain(subs.get(0), merged);
+			}
+		}
+		if (!merged.isEmpty()) {
+			merged.add(node);
+			StringBuilder sb = new StringBuilder();
+			for (int i = 0; i < merged.size(); i++) {
+				if (i > 0) {
+					sb.append('/');
+				}
+				sb.append(merged.get(i).shortName);
+			}
+			node.shortName = sb.toString();
+		}
+		return node;
+	}
+
 	@Override
 	public boolean hasContent() {
 		return resFile != null;

jadx-gui/src/main/java/jadx/gui/treemodel/JRoot.java

@@ -73,6 +73,7 @@ public class JRoot extends JNode {
 			JResource leaf = new JResource(rf, rf.getDeobfName(), parts[count - 1], JResType.FILE);
 			curRf.addSubNode(leaf);
 		}
+		JResource.mergeMiddleDirs(root);
 		root.sortSubNodes();
 		root.update();
 		return root;

jadx-gui/src/main/java/jadx/gui/utils/res/ResTableHelper.java

@@ -24,6 +24,7 @@ public class ResTableHelper {
 	public static List<JResource> buildTree(JResource resTableRes, ResContainer resTable) {
 		ResTableHelper resTableHelper = new ResTableHelper(resTableRes);
 		resTableHelper.process(resTable);
+		JResource.mergeMiddleDirs(resTableHelper.roots);
 		return resTableHelper.roots;
 	}