fix: three Tradier sandbox incident fixes (2026-07-28 reject loop)

Incident: entry-timeout cancels raced lazy sandbox fills -> untracked
positions; naked-stop guard then force-sold but every sell rejected
('more shares than your current long position') for hours.

1. translate_order: Tradier OTOCO/OTO parents carry no top-level
   symbol/side/qty (legs only) — inherit from the entry leg so
   symbol-scoped lookups can see brackets; get_orders symbols filter
   also matches by leg symbols. Without this the stop-leg search read
   a fully-protected position as naked.
2. close_position: cancel the symbol's resting sell orders/legs first —
   Tradier reserves held shares against open sells, so selling without
   releasing them always rejects.
3. cancel_entry (broker-agnostic): after cancelling, re-check the
   broker's final word by client_order_id; journal a fill for any
   executed shares instead of orphaning a real position (2026-07-06
   class, same race exists on Alpaca).

49 tests pass incl. new coverage for all three.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

alpaca_paper/execution.py

@@ -251,16 +251,57 @@ class AlpacaPaperExecutor:
     def cancel_entry(
         self, order_id: str, broker_order_id: str | None, symbol: str, reason: str
     ) -> ExecutionResult:
-        """Cancel a resting (unfilled) entry order at the broker and record it."""
+        """Cancel a resting (unfilled) entry order at the broker and record it.
+
+        CANCEL-vs-FILL RACE: the entry can fill at the broker before (or as)
+        the cancel lands — the cancel then no-ops but journaling only a cancel
+        orphans a REAL position (untracked shares, the 2026-07-06 class;
+        happened live on Tradier sandbox 2026-07-28: lazy fills + entry
+        timeouts). After cancelling, re-check the broker's final word and emit
+        the fill for any executed shares so the position is tracked."""
         try:
             if broker_order_id:
                 self.client.cancel_order(broker_order_id)
         except AlpacaApiError as exc:
             # already filled/cancelled at the broker, or transient — log and
-            # still emit the cancel so our state stops tracking it
+            # continue to the fill-race check below
             logger.warning("cancel of %s returned: %s", order_id, exc)
         except Exception as exc:  # noqa: BLE001
             logger.warning("cancel of %s errored: %s", order_id, exc)
+
+        filled_qty, fill_price, side = 0, None, "buy"
+        getter = getattr(self.client, "get_order_by_client_order_id", None)
+        if getter is not None:
+            try:
+                found = getter(order_id[:48]) or {}
+                filled_qty = int(float(found.get("filled_qty") or 0))
+                fill_price = float(found.get("filled_avg_price") or 0) or None
+                side = found.get("side") or "buy"
+            except Exception:  # noqa: BLE001 — lookup failure: keep cancel-only path
+                pass
+
+        if filled_qty > 0:
+            logger.warning("cancel of %s raced a fill: %d %s executed @ %s — "
+                           "journaling the fill", order_id, filled_qty, symbol, fill_price)
+            self.store.emit(
+                OrderFilledEvent(
+                    timestamp=datetime.now(),
+                    mode=self.mode,
+                    correlation_id=self.session_id,
+                    message=f"Filled {symbol} {filled_qty} @ {fill_price} "
+                            f"(cancel raced fill)",
+                    symbol=symbol,
+                    order_id=order_id,
+                    fill_price=fill_price or 0.0,
+                    fill_quantity=filled_qty,
+                    side=side,
+                    payload={"symbol": symbol, "order_id": order_id,
+                             "fill_price": fill_price, "fill_quantity": filled_qty,
+                             "side": side, "cancel_raced_fill": True},
+                )
+            )
+            return ExecutionResult(ok=True, order_id=order_id, status="filled")
+
         self._emit_cancelled(
             ExecutionRequest(symbol=symbol, side="buy", quantity=0, order_id=order_id),
             reason,