fix: npx 擴充功能 Windows 路徑解析問題修復、自動確認安裝提示

1. npx 命令解析重構
   - Extension.cs：新增 ResolveNpxCommand 方法，繞過 npx.cmd/npx shell 腳本直接用 node 執行 npx-cli.js
   - Extension.cs：新增 FindNpxCliPath 方法，在 PATH 中搜尋 node 安裝路徑並定位 npx-cli.js
   - Extension.cs：ResolveCommand 方法 npx 類型改為呼叫 ResolveNpxCommand

2. npx 執行優化
   - Extension.cs：自動添加 --yes 參數，避免安裝確認提示導致非互動式執行卡住
   - Extension.cs：統一所有平台（Windows/macOS/Linux）使用相同的 node npx-cli.js 策略
   - Extension.cs：保留 fallback 機制，找不到 npx-cli.js 時仍使用原生 npx/npx.cmd

Author: JaJa

Core/Extension/Extension.cs

@@ -1416,14 +1416,72 @@ private static CommandResolution ResolveCommand(ExtensionCommand command)
             "python" => new CommandResolution(isWindows ? "python.exe" : "python3",
                 PrependExecutable(executable, argumentList)),
             "dotnet" => new CommandResolution("dotnet", PrependExecutable(executable, argumentList)),
-            "npx" => new CommandResolution(isWindows ? "npx.cmd" : "npx",
-                PrependExecutable(executable, argumentList)),
+            "npx" => ResolveNpxCommand(executable, argumentList),
             "pipx" => new CommandResolution(isWindows ? "pipx.exe" : "pipx",
                 PrependRun(executable, argumentList)),
             _ => new CommandResolution(executable, argumentList)
         };
     }
 
+    /// <summary>
+    ///     Resolves npx command by directly executing npx-cli.js with node to avoid
+    ///     shell script path resolution issues when executed via Process.Start.
+    ///     Adds --yes flag to auto-confirm package installation since extensions
+    ///     run non-interactively and cannot respond to prompts.
+    /// </summary>
+    /// <param name="packageName">The npm package name to execute.</param>
+    /// <param name="arguments">Additional arguments for the package.</param>
+    /// <returns>A <see cref="CommandResolution" /> for npx execution.</returns>
+    private static CommandResolution ResolveNpxCommand(string packageName, List<string> arguments)
+    {
+        var npxArgs = new List<string>(arguments.Count + 2) { "--yes", packageName };
+        npxArgs.AddRange(arguments);
+
+        var isWindows = OperatingSystem.IsWindows();
+        var npxCliPath = FindNpxCliPath(isWindows);
+
+        if (npxCliPath != null)
+        {
+            var args = new List<string>(npxArgs.Count + 1) { npxCliPath };
+            args.AddRange(npxArgs);
+            return new CommandResolution(isWindows ? "node.exe" : "node", args);
+        }
+
+        return new CommandResolution(isWindows ? "npx.cmd" : "npx", npxArgs);
+    }
+
+    /// <summary>
+    ///     Finds the path to npx-cli.js by searching PATH for node installation.
+    /// </summary>
+    /// <param name="isWindows">Whether the current platform is Windows.</param>
+    /// <returns>The full path to npx-cli.js, or null if not found.</returns>
+    private static string? FindNpxCliPath(bool isWindows)
+    {
+        var pathEnv = Environment.GetEnvironmentVariable("PATH");
+        if (string.IsNullOrEmpty(pathEnv))
+            return null;
+
+        var nodeExeName = isWindows ? "node.exe" : "node";
+        var paths = pathEnv.Split(Path.PathSeparator, StringSplitOptions.RemoveEmptyEntries);
+
+        foreach (var path in paths)
+            try
+            {
+                var nodePath = Path.Combine(path, nodeExeName);
+                if (!File.Exists(nodePath))
+                    continue;
+
+                var npxCliPath = Path.Combine(path, "node_modules", "npm", "bin", "npx-cli.js");
+                if (File.Exists(npxCliPath))
+                    return npxCliPath;
+            }
+            catch
+            {
+            }
+
+        return null;
+    }
+
     /// <summary>
     ///     Prepends the executable path to the argument list.
     /// </summary>