feat(V2): IBKR streaming tools (tick/depth/subscribe)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tests/unit/exchanges/ibkr/test_tools.py

@@ -26,3 +26,22 @@ async def test_get_account_tool_calls_client():
     client.get_account = AsyncMock(return_value={"netliquidation": {"amount": 10000}})
     res = await t.get_account(client, t.GetAccountReq())
     assert res["netliquidation"]["amount"] == 10000
+
+
+@pytest.mark.asyncio
+async def test_get_tick_uses_cache_or_subscribes():
+    client = MagicMock()
+    client.resolve_conid = AsyncMock(return_value=42)
+    ws = MagicMock()
+    ws.get_tick_snapshot = MagicMock(side_effect=[
+        None,
+        {"conid": 42, "last_price": 99.5, "bid": 99.4, "ask": 99.6,
+         "bid_size": 1, "ask_size": 1, "timestamp_ms": 1700000000000},
+    ])
+    ws.subscribe_tick = AsyncMock()
+
+    res = await t.get_tick(
+        client, t.GetTickReq(symbol="AAPL"), ws=ws, timeout_s=0.05,
+    )
+    assert res["last_price"] == 99.5
+    ws.subscribe_tick.assert_awaited_once_with(42)