feat(ServerModal, serverUtils): implement conditional tunnel selection based on server type; add needsTunnel utility function for improved server configuration

frontend/src/components/server/ServerModal.jsx

@@ -4,6 +4,7 @@ import {
   makeGateway, 
   normalizeGateways, 
   needsGateways as NEEDS_GATEWAYS,
+  needsTunnel as NEEDS_TUNNEL,
   SERVER_TYPE_OPTIONS,
   TUNNEL_TYPES
 } from '../../utils/serverUtils.js';
@@ -417,7 +418,7 @@ function ServerModal({ show, mode = 'add', server, onSave, onClose, error: exter
                 )}
 
                 {/* Тип сервера */}
-                <div className="col-md-6">
+                <div className={NEEDS_TUNNEL(localServer.type) ? "col-md-6" : "col-12"}>
                   <label className="form-label required">Тип сервера</label>
                   <select
                     className="form-select"
@@ -433,20 +434,22 @@ function ServerModal({ show, mode = 'add', server, onSave, onClose, error: exter
                   </select>
                 </div>
 
-                {/* Тип туннеля */}
-                <div className="col-md-6">
-                  <label className="form-label required">Тип туннеля</label>
-                  <select
-                    className="form-select"
-                    value={localServer.tunnel || 'GRE'}
-                    onChange={(e) => handleFieldChange('tunnel', e.target.value)}
-                    required
-                  >
-                    {TUNNEL_TYPES.map((t) => (
-                      <option key={t} value={t}>{t}</option>
-                    ))}
-                  </select>
-                </div>
+                {/* Тип туннеля - только для типов, которым он нужен */}
+                {NEEDS_TUNNEL(localServer.type) && (
+                  <div className="col-md-6">
+                    <label className="form-label required">Тип туннеля</label>
+                    <select
+                      className="form-select"
+                      value={localServer.tunnel || 'GRE'}
+                      onChange={(e) => handleFieldChange('tunnel', e.target.value)}
+                      required
+                    >
+                      {TUNNEL_TYPES.map((t) => (
+                        <option key={t} value={t}>{t}</option>
+                      ))}
+                    </select>
+                  </div>
+                )}
 
                 {/* Основной шлюз (текстовое поле для совместимости) */}
                 <div className="col-12">