fix: exclude dynamic valuation tags from IBKR cash evidence

application/broker_reconciliation.py

@@ -39,6 +39,18 @@ class IBKRReconciliationReadError(RuntimeError):
     "local_execution_ledger_sha256",
 )
 
+# These are actual cash-balance tags, in the same order as the execution
+# snapshot's cash selector.  Margin capacity and mark-to-market account tags
+# (for example AvailableFunds and NetLiquidation) must never enter a recovery
+# digest: they legitimately move while no cash, order, or position changes.
+_CASH_BALANCE_TAG_PRIORITY = (
+    "$LEDGER-CashBalance",
+    "$LEDGER-TotalCashBalance",
+    "CashBalance",
+    "TotalCashBalance",
+    "SettledCash",
+)
+
 
 def _text(value: object) -> str:
     return str(value or "").strip()
@@ -125,11 +137,16 @@ def _normalise_cash_balance(value: Mapping[str, object], *, selected_account_ids
         for tag, number in value.items()
         if _text(tag) not in {"account_id", "currency"}
     }
-    return {
-        "account": account_id,
-        "currency": _text(value.get("currency")).upper(),
-        "tags": dict(sorted(numeric_tags.items())),
-    }
+    for tag in _CASH_BALANCE_TAG_PRIORITY:
+        if tag in numeric_tags:
+            return {
+                "account": account_id,
+                "currency": _text(value.get("currency")).upper(),
+                "tags": {tag: numeric_tags[tag]},
+            }
+    raise IBKRReconciliationReadError(
+        "IBKR reconciliation is missing a stable cash-balance tag."
+    )
 
 
 def _open_trade_account(trade: Any) -> object:

docs/ibkr_reconciliation_baseline_enrollment.zh-CN.md

@@ -104,3 +104,7 @@ Scheduler 任务，再由既有的最小权限 Scheduler 身份调用冻结服
 同一目标至少应在相隔一分钟的两次手动运行中得到候选，才能交给
 `build_reconciliation_baseline_candidate.py`。工作流的成功只说明读取和收据格式正常；
 候选仍可能因为未配置预期摘要或账本差异而正确保持阻断。
+
+其中现金摘要只选择结算/账面现金标签（例如 `CashBalance`），不会把随市价变化的
+`NetLiquidation` 或保证金可用额计入。这样没有现金、订单或仓位变化的账户不会因为正常
+估值波动而被误判为基线漂移；没有可靠现金标签时仍会失败关闭。

tests/test_broker_reconciliation.py

@@ -120,6 +120,79 @@ def fetch_portfolio_snapshot(_ib, **kwargs):
     assert observations.open_orders[0]["account"] == "U123"
 
 
+def test_cash_reconciliation_ignores_dynamic_margin_and_valuation_tags() -> None:
+    def fetch_snapshot(_ib, *, dynamic_net_liquidation: float, dynamic_available_funds: float, **_kwargs):
+        return SimpleNamespace(
+            positions=(),
+            metadata={
+                "cash_balances": (
+                    {
+                        "account_id": "U123",
+                        "currency": "USD",
+                        "CashBalance": 123.45,
+                        "AvailableFunds": dynamic_available_funds,
+                        "NetLiquidation": dynamic_net_liquidation,
+                    },
+                ),
+                "option_positions": (),
+            },
+        )
+
+    ib = _IB()
+    first = collect_read_only_reconciliation_observations(
+        ib,
+        account_ids=("U123",),
+        fetch_portfolio_snapshot=lambda *args, **kwargs: fetch_snapshot(
+            *args,
+            **kwargs,
+            dynamic_net_liquidation=1_000.0,
+            dynamic_available_funds=700.0,
+        ),
+        market_currency="USD",
+        cash_only_execution=True,
+    )
+    second = collect_read_only_reconciliation_observations(
+        ib,
+        account_ids=("U123",),
+        fetch_portfolio_snapshot=lambda *args, **kwargs: fetch_snapshot(
+            *args,
+            **kwargs,
+            dynamic_net_liquidation=1_050.0,
+            dynamic_available_funds=750.0,
+        ),
+        market_currency="USD",
+        cash_only_execution=True,
+    )
+
+    assert first.cash == second.cash == (
+        {"account": "U123", "currency": "USD", "tags": {"CashBalance": 123.45}},
+    )
+
+
+def test_cash_reconciliation_fails_closed_without_a_cash_balance_tag() -> None:
+    with pytest.raises(IBKRReconciliationReadError, match="stable cash-balance tag"):
+        collect_read_only_reconciliation_observations(
+            _IB(),
+            account_ids=("U123",),
+            fetch_portfolio_snapshot=lambda *_args, **_kwargs: SimpleNamespace(
+                positions=(),
+                metadata={
+                    "cash_balances": (
+                        {
+                            "account_id": "U123",
+                            "currency": "USD",
+                            "AvailableFunds": 700.0,
+                            "NetLiquidation": 1_000.0,
+                        },
+                    ),
+                    "option_positions": (),
+                },
+            ),
+            market_currency="USD",
+            cash_only_execution=True,
+        )
+
+
 def test_missing_read_only_order_surface_fails_closed() -> None:
     class MissingOpenOrderReader(_IB):
         reqAllOpenOrders = None