fix: 安全性与代码质量加固（异常保护、外键级联、竞态修复、优雅关机）

src/web/hooks/useTrend.ts

@@ -1,21 +1,27 @@
-import { useCallback, useState } from "react";
+import { useCallback, useRef, useState } from "react";
 import type { TrendPoint } from "../../shared/api";
 
 export function useTrend(targetId: number | null) {
   const [data, setData] = useState<TrendPoint[]>([]);
   const [error, setError] = useState<string | null>(null);
   const [loading, setLoading] = useState(false);
+  const abortRef = useRef<AbortController | null>(null);
 
   const fetchTrend = useCallback(
     async (from: string, to: string) => {
       if (targetId === null) return;
 
+      abortRef.current?.abort();
+      const controller = new AbortController();
+      abortRef.current = controller;
+
       setLoading(true);
       setError(null);
 
       try {
         const response = await fetch(
           `/api/targets/${targetId}/trend?from=${encodeURIComponent(from)}&to=${encodeURIComponent(to)}`,
+          { signal: controller.signal },
         );
 
         if (!response.ok) throw new Error(`HTTP ${response.status}`);
@@ -23,6 +29,7 @@ export function useTrend(targetId: number | null) {
         const result = (await response.json()) as TrendPoint[];
         setData(result);
       } catch (err) {
+        if (err instanceof DOMException && err.name === "AbortError") return;
         setError(err instanceof Error ? err.message : "请求失败");
       } finally {
         setLoading(false);