Add Binance SIM market adapter and exchange switch in settings.

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

backend/tests/test_binance_parse.py

@@ -0,0 +1,59 @@
+"""币安符号解析与中性到期工具测试。"""
+
+from app.exchange.binance.parse import parse_option_symbol, rows_to_option_contracts
+from app.exchange.expiry import expiry_ms_from_ymd, ymd_from_expiry_ms
+from app.exchange.runtime import normalize_exchange_name
+
+
+def test_binance_parse_option_symbol() -> None:
+    y, stk, side = parse_option_symbol("ETH-250726-1860-C")
+    assert y == "250726"
+    assert stk == 1860.0
+    assert side == "C"
+    y2, _, side2 = parse_option_symbol("ETH-250726-1860-P")
+    assert y2 == "250726" and side2 == "P"
+    assert parse_option_symbol("ETHUSDT")[0] is None
+
+
+def test_binance_rows_to_contracts() -> None:
+    rows = [
+        {
+            "symbol": "ETH-250726-1860-C",
+            "status": "TRADING",
+            "strikePrice": "1860",
+            "side": "CALL",
+            "expiryDate": expiry_ms_from_ymd("250726"),
+            "unit": "1",
+            "underlying": "ETHUSDT",
+        },
+        {
+            "symbol": "ETH-250726-1860-P",
+            "status": "TRADING",
+            "strikePrice": "1860",
+            "side": "PUT",
+            "expiryDate": expiry_ms_from_ymd("250726"),
+            "unit": 1,
+            "underlying": "ETHUSDT",
+        },
+    ]
+    out = rows_to_option_contracts(rows)
+    assert len(out) == 2
+    assert out[0]["expiry_ymd"] == "250726"
+    assert out[0]["ct_mult"] == 1.0
+    assert out[0]["side"] in ("C", "P")
+
+
+def test_expiry_ms_roundtrip() -> None:
+    ms = expiry_ms_from_ymd("250726")
+    assert ymd_from_expiry_ms(ms) == "250726"
+    # UTC 08:00
+    from datetime import datetime, timezone
+
+    dt = datetime.fromtimestamp(ms / 1000, tz=timezone.utc)
+    assert dt.hour == 8 and dt.minute == 0
+
+
+def test_normalize_exchange() -> None:
+    assert normalize_exchange_name("BN") == "binance"
+    assert normalize_exchange_name("okx") == "okx"
+    assert normalize_exchange_name(None) == "okx"