fix: add SignalHistoryItem and snapshots types to api.ts

frontend/app/live/page.tsx

@@ -1,19 +1,12 @@
 "use client";
 
 import { useEffect, useState, useCallback } from "react";
+import { api } from "@/lib/api";
 import {
   LineChart, Line, XAxis, YAxis, Tooltip, Legend,
   ResponsiveContainer, ReferenceLine, CartesianGrid
 } from "recharts";
 
-interface Snapshot {
-  ts: number;
-  btc_rate: number;
-  eth_rate: number;
-  btc_price: number;
-  eth_price: number;
-}
-
 interface ChartPoint {
   time: string;
   btcRate: number;
@@ -30,9 +23,8 @@ export default function LivePage() {
 
   const fetchSnapshots = useCallback(async () => {
     try {
-      const r = await fetch(`/api/snapshots?hours=${hours}&limit=3600`);
-      const json = await r.json();
-      const rows: Snapshot[] = json.data || [];
+      const json = await api.snapshots(hours, 3600);
+      const rows = json.data || [];
       setCount(json.count || 0);
       // 降采样：每30条取1条，避免图表过密
       const step = Math.max(1, Math.floor(rows.length / 300));

frontend/lib/api.ts

@@ -37,6 +37,33 @@ export interface StatsResponse {
   combo: { mean7d: number; annualized: number };
 }
 
+export interface SignalHistoryItem {
+  id: number;
+  symbol: string;
+  rate: number;
+  annualized: number;
+  sent_at: string;
+  message: string;
+}
+
+export interface SignalsHistoryResponse {
+  items: SignalHistoryItem[];
+}
+
+export interface SnapshotItem {
+  ts: number;
+  btc_rate: number;
+  eth_rate: number;
+  btc_price: number;
+  eth_price: number;
+}
+
+export interface SnapshotsResponse {
+  count: number;
+  hours: number;
+  data: SnapshotItem[];
+}
+
 async function fetchAPI<T>(path: string): Promise<T> {
   const res = await fetch(`${API_BASE}${path}`, { cache: "no-store" });
   if (!res.ok) throw new Error(`API error ${res.status}`);
@@ -48,4 +75,7 @@ export const api = {
   history: () => fetchAPI<HistoryResponse>("/api/history"),
   stats: () => fetchAPI<StatsResponse>("/api/stats"),
   health: () => fetchAPI<{ status: string }>("/api/health"),
+  signalsHistory: () => fetchAPI<SignalsHistoryResponse>("/api/signals/history"),
+  snapshots: (hours = 24, limit = 5000) =>
+    fetchAPI<SnapshotsResponse>(`/api/snapshots?hours=${hours}&limit=${limit}`),
 };