Add BTC/ETH spot tickers on nav, anchored to Beijing 08:00 open.

Co-authored-by: Cursor <cursoragent@cursor.com>

app.py

@@ -5660,6 +5660,29 @@ def api_settings_open_guard():
     )
 
 
+@app.route("/api/nav_spot_tickers")
+@login_required
+def api_nav_spot_tickers():
+    """BTC/ETH 现货最新价,相对北京时间 08:00(OKX 日K开盘)涨跌."""
+    try:
+        from lib.market.nav_spot_tickers_lib import build_nav_spot_tickers
+
+        tickers = build_nav_spot_tickers(
+            exchange,
+            reset_hour=TRADING_DAY_RESET_HOUR,
+            now_fn=lambda: datetime.now(APP_TZ),
+        )
+        return jsonify(
+            {
+                "ok": True,
+                "updated_at": app_now_str(),
+                "tickers": tickers,
+            }
+        )
+    except Exception as e:
+        return jsonify({"ok": False, "msg": str(e) or "行情读取失败", "tickers": []}), 502
+
+
 @app.route("/api/price_snapshot")
 @login_required
 def api_price_snapshot():