fix(ui): подтверждать переключение туннелей GRE

app/(main)/gre/page.tsx

@@ -275,6 +275,9 @@ function GrePageContent({ selectedServerId, selectedTunnelId, allTunnelsHref, on
   const [tunnelMode,      setTunnelMode]      = useState<"create" | "edit">("create")
   const [editingTunnel,   setEditingTunnel]   = useState<GreTunnel | null>(null)
   const [pendingDelete,   setPendingDelete]   = useState<GreTunnel | null>(null)
+  const toggleLock = useRef(false)
+  const [toggleStatus, setToggleStatus] = useState<string | null>(null)
+  const [toggleError, setToggleError] = useState<string | null>(null)
   const deleteLock = useRef(false)
   const [deleteError, setDeleteError] = useState<string | null>(null)
   const [mutateBusy,      setMutateBusy]      = useState(false)
@@ -484,10 +487,13 @@ function GrePageContent({ selectedServerId, selectedTunnelId, allTunnelsHref, on
   }
 
   async function toggleTunnel(t: GreTunnel) {
-    if (!isLive || mutationsLocked) return
+    if (!isLive || mutationsLocked || toggleLock.current) return
+    toggleLock.current = true
+    setToggleError(null)
+    setToggleStatus(`Ожидание изменения ${t.name}…`)
     setMutateBusy(true)
     try {
-      await apiFetch("/api/gre/tunnels", {
+      const result = await apiFetch<{ ok: boolean }>("/api/gre/tunnels", {
         method: "PATCH",
         body: JSON.stringify({
           serverId: t.serverId,
@@ -497,11 +503,14 @@ function GrePageContent({ selectedServerId, selectedTunnelId, allTunnelsHref, on
           remoteAddress: t.remoteAddress,
         }),
       })
+      if (result?.ok !== true) throw new Error("Сервер не подтвердил изменение туннеля")
       toast.success(t.enabled ? `Выключен ${t.name}` : `Включён ${t.name}`)
       await loadLive()
     } catch (err) {
-      toast.error("Не удалось изменить туннель", { description: String(err) })
+      setToggleError(`${t.name}: ${err instanceof Error ? err.message : "Не удалось изменить туннель"}`)
     } finally {
+      toggleLock.current = false
+      setToggleStatus(null)
       setMutateBusy(false)
     }
   }
@@ -719,6 +728,9 @@ function GrePageContent({ selectedServerId, selectedTunnelId, allTunnelsHref, on
             ]}
           />
 
+          {toggleStatus && <p role="status" className="text-sm text-muted-foreground">{toggleStatus}</p>}
+          {toggleError && <p role="alert" className="text-sm text-destructive">{toggleError}</p>}
+
           {/* Page tabs */}
           <div className="flex items-center gap-1 border-b">
             {(["tunnels", "pools"] as PageTab[]).map((tab) => (