refactor(api): implement abort signal handling in API requests across multiple components to improve cancellation of ongoing requests and prevent memory leaks

frontend/src/IPRangesManager.jsx

@@ -114,13 +114,23 @@ function IPRangesManager() {
   const [wsUrl, setWsUrl] = useState('');
 
   useEffect(() => {
-    (async () => { try { const r = await api.get('/ws/url'); setWsUrl(String(r.data?.url || '')); } catch {} })();
+    const controller = new AbortController();
+    (async () => {
+      try {
+        const r = await api.get('/ws/url', { signal: controller.signal });
+        setWsUrl(String(r.data?.url || ''));
+      } catch (e) {
+        if (e?.name === 'CanceledError' || e?.name === 'AbortError' || e?.code === 'ERR_CANCELED') return;
+      }
+    })();
+    return () => controller.abort();
   }, []);
 
-  const fetchItems = async () => {
+  const fetchItems = async (abortSignal) => {
     setLoading(true);
+    const opts = abortSignal ? { signal: abortSignal } : {};
     try {
-      const response = await api.get(`/ip-ranges`, { params: { offset: 0, limit: 0, format: 'std' } });
+      const response = await api.get(`/ip-ranges`, { params: { offset: 0, limit: 0, format: 'std' }, ...opts });
       const payload = Array.isArray(response.data?.items) ? response.data.items : [];
       const total = payload.length;
       setItems(payload);
@@ -132,6 +142,7 @@ function IPRangesManager() {
       setContentLength(typeof lengthHeader !== 'undefined' ? Number(lengthHeader) : null);
       setError('');
     } catch (error) {
+      if (error?.name === 'CanceledError' || error?.name === 'AbortError' || error?.code === 'ERR_CANCELED') return;
       console.error('Error fetching ip-ranges:', error);
       setError('Не удалось загрузить IP-диапазоны. Проверьте, запущен ли бэкенд.');
     } finally {
@@ -139,7 +150,14 @@ function IPRangesManager() {
     }
   };
 
-  useEffect(() => { if (!didInit.current) { didInit.current = true; fetchItems(); } }, []);
+  useEffect(() => {
+    if (!didInit.current) {
+      didInit.current = true;
+      const controller = new AbortController();
+      fetchItems(controller.signal);
+      return () => controller.abort();
+    }
+  }, []);
 
   const handleAddItem = (item) => {
     const ipRange = item?.ipRange || newItem.ipRange;