Fetch native exchange OHLCV per timeframe instead of local aggregation.

Store and serve 15m/2h/4h directly from the exchange so market charts match venue candles.

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

tests/test_hub_kline_store.py

@@ -130,14 +130,14 @@ class TestHubKlineStore(unittest.TestCase):
         self.assertTrue(out.get("ok"))
         self.assertEqual(len(out.get("candles") or []), 300)
 
-    def test_resolve_15m_from_5m_aggregate(self):
+    def test_resolve_15m_reads_native_bars(self):
         init_db(self.db)
         now = int(time.time() * 1000)
-        period = TIMEFRAME_MS["5m"]
-        last_closed = last_closed_bar_open_ms("5m", now)
+        period = TIMEFRAME_MS["15m"]
+        last_closed = last_closed_bar_open_ms("15m", now)
         bars = []
-        for i in range(30):
-            oms = last_closed - (29 - i) * period
+        for i in range(12):
+            oms = last_closed - (11 - i) * period
             bars.append(
                 {
                     "open_time_ms": oms,
@@ -148,7 +148,7 @@ class TestHubKlineStore(unittest.TestCase):
                     "volume": 10.0,
                 }
             )
-        upsert_bars("okx", "ETH/USDT", "5m", bars, self.db)
+        upsert_bars("okx", "ETH/USDT", "15m", bars, self.db)
 
         def remote_fetch(**kwargs):
             self.fail("不应请求交易所")
@@ -159,11 +159,12 @@ class TestHubKlineStore(unittest.TestCase):
             "15m",
             remote_fetch,
             db_path=self.db,
-            limit=5,
+            limit=10,
         )
         self.assertTrue(out.get("ok"))
-        self.assertEqual(out.get("source"), "aggregate")
-        self.assertGreaterEqual(len(out.get("candles") or []), 5)
+        self.assertEqual(out.get("source"), "db")
+        self.assertEqual(out.get("storage_timeframe"), "15m")
+        self.assertGreaterEqual(len(out.get("candles") or []), 10)
 
     def test_load_bars_before(self):
         init_db(self.db)