文件管理: 添加缺失的路径输入框 + Enter键触发浏览

- 添加dirPath输入框(之前只有JS引用没有DOM元素)
- Enter键支持快速跳转到指定路径
- 输入框预填默认值'/'

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web/app/files.html

@@ -11,6 +11,7 @@
         <select id="serverSelect" class="px-3 py-1.5 bg-slate-800 border border-slate-700 rounded-lg text-white text-sm">
           <option value="">-- 选择服务器 --</option>
         </select>
+        <input id="dirPath" type="text" value="/" placeholder="/ 路径" class="px-3 py-1.5 bg-slate-800 border border-slate-700 rounded-lg text-white text-sm placeholder-slate-500 focus:outline-none focus:ring-2 focus:ring-brand w-48">
         <button onclick="browseDir()" class="px-3 py-1.5 bg-brand hover:bg-brand-dark text-white text-sm rounded-lg transition">浏览</button>
       </div>
     </header>
@@ -109,6 +110,10 @@
     }
 
     function esc(s){if(!s)return'';const d=document.createElement('div');d.textContent=s;return d.innerHTML}
+
+    // Enter key in path input triggers browse
+    document.getElementById('dirPath').addEventListener('keydown',e=>{if(e.key==='Enter')browseDir()});
+
     loadServers();
   </script>
 </body></html>