Clarify server nav labels (Default Server Interface vs All Servers)

No route/logic changes - pure label cleanup so the legacy default-server
editor and the multi-server management page are no longer confusable.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

templates/base.html

@@ -132,7 +132,7 @@
                             <a href="{{.basePath}}/wg-server" class="nav-link {{if eq .baseData.Active "wg-server" }}active{{end}}">
                                 <i class="nav-icon fas fa-server"></i>
                                 <p>
-                                    Wireguard Server
+                                    Default Server Interface
                                 </p>
                             </a>
                         </li>
@@ -143,7 +143,7 @@
                             <a href="{{.basePath}}/servers-settings" class="nav-link {{if eq .baseData.Active "servers" }}active{{end}}">
                                 <i class="nav-icon fas fa-server"></i>
                                 <p>
-                                    Servers
+                                    All Servers
                                 </p>
                             </a>
                         </li>

templates/server.html

@@ -1,5 +1,5 @@
 {{define "title"}}
-Wireguard Server
+Default Server Interface
 {{end}}
 
 {{define "top_css"}}
@@ -10,13 +10,13 @@ Wireguard Server
 {{end}}
 
 {{define "page_title"}}
-Wireguard Server Settings
+Default Server Interface Settings
 {{end}}
 
 {{define "page_content"}}
 <section class="content">
     <div class="container-fluid">
-        <!-- <h5 class="mt-4 mb-2">Wireguard Server</h5> -->
+        <!-- <h5 class="mt-4 mb-2">Default Server Interface</h5> -->
         <div class="row">
             <!-- left column -->
             <div class="col-md-6">

templates/servers.html

@@ -1,5 +1,5 @@
 {{define "title"}}
-Servers
+All Servers
 {{end}}
 
 {{define "top_css"}}
@@ -10,7 +10,7 @@ Servers
 {{end}}
 
 {{define "page_title"}}
-Servers
+All Servers
 {{end}}
 
 {{define "page_content"}}