fix: DisplayPath 所有层级加#N去重 + 移除旧格式兼容

- BuildNode 不再剥离父路径#N后缀
- FromModelItem 对每层祖先计算 siblingIndex 追加#N，与树加载一致
- 解决复制子树中节点别名泄露给其他子树的问题
- FromKey 移除纯 DisplayPath 旧格式兼容

src/Core/AliasTree/AliasNodeIdentity.cs

@@ -17,9 +17,6 @@ namespace NavisworksTransport.Core.AliasTree
     ///   可读可调试，IndexPath 失效时作为降级定位手段。
     ///
     /// 序列化格式（ToKey）： "IndexPath||DisplayPath"
-    /// 示例： "0,2,5,1||模型/楼层/墙#0"
-    ///
-    /// 向后兼容：不含 "||" 的 key 按旧格式（纯 DisplayPath）解析。
     /// </summary>
     public readonly struct AliasNodeIdentity : IEquatable<AliasNodeIdentity>
     {
@@ -66,22 +63,17 @@ namespace NavisworksTransport.Core.AliasTree
                 indexPath = string.Empty;
             }
 
-            // 2. DisplayPath — 父链 DisplayName + 同级索引
+            // 2. DisplayPath — 父链 DisplayName + 每层同名去重索引
             var parts = new List<string>();
             var current = item;
             while (current != null)
             {
-                parts.Insert(0, current.DisplayName ?? "?");
+                int siblingIdx = ComputeSiblingIndex(current);
+                string name = current.DisplayName ?? "?";
+                parts.Insert(0, siblingIdx > 0 ? $"{name}#{siblingIdx}" : name);
                 current = current.Parent;
             }
-            string displayPath = string.Join("/", parts);
-
-            // 3. 同级同名节点去重索引
-            int siblingIndex = ComputeSiblingIndex(item);
-
-            string displayPathWithIndex = siblingIndex > 0
-                ? $"{displayPath}#{siblingIndex}"
-                : displayPath;
+            string displayPathWithIndex = string.Join("/", parts);
 
             return new AliasNodeIdentity(indexPath, displayPathWithIndex);
         }
@@ -129,10 +121,11 @@ namespace NavisworksTransport.Core.AliasTree
             if (string.IsNullOrEmpty(key))
                 throw new ArgumentException("key 不能为空", nameof(key));
 
-            // 检查是否有双字段分隔符
+            // key 必须包含 "||" 分隔符
             int separatorIndex = key.IndexOf("||", StringComparison.Ordinal);
-            if (separatorIndex >= 0)
-            {
+            if (separatorIndex < 0)
+                throw new FormatException($"key 缺少 || 分隔符: {key}");
+
             string indexPath = key.Substring(0, separatorIndex);
             string displayPath = key.Substring(separatorIndex + 2);
             if (string.IsNullOrEmpty(displayPath))
@@ -140,10 +133,6 @@ namespace NavisworksTransport.Core.AliasTree
             return new AliasNodeIdentity(indexPath, displayPath);
         }
 
-            // 向后兼容：纯 DisplayPath 格式（旧数据）
-            return new AliasNodeIdentity(string.Empty, key);
-        }
-
         /// <summary>
         /// 提前验证 key 字符串格式是否合法
         /// </summary>

src/UI/WPF/Views/AliasTreeControl.xaml.cs

@@ -355,14 +355,6 @@ namespace NavisworksTransport.UI.WPF.Views
             string parentPath = parentDisplayPath;
             int sepIdx = parentPath.IndexOf("||", StringComparison.Ordinal);
             if (sepIdx >= 0) parentPath = parentPath.Substring(sepIdx + 2);
-            // 去掉结尾的 #数字 后缀（中间层不加 siblingIndex）
-            int hashIdx = parentPath.LastIndexOf('#');
-            if (hashIdx > 0)
-            {
-                string suffix = parentPath.Substring(hashIdx + 1);
-                bool isNumeric = suffix.Length > 0 && suffix.All(char.IsDigit);
-                if (isNumeric) parentPath = parentPath.Substring(0, hashIdx);
-            }
             string displayPath = string.IsNullOrEmpty(parentPath)
                 ? displayName
                 : parentPath + "/" + displayName;