Fix: parking buy fill confirmation blocks event loop with 5s hard timeout

Make _parking_buy async (asyncio.sleep instead of time.sleep) and extend
confirmation from 5s to 30s per attempt with up to 3 retries on timeout.
On timeout, cancels the stale order before retrying with fresh price data.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/paper_trader/engine.py

@@ -5,6 +5,7 @@ Order execution (HOW to execute) is done via Alpaca Paper Trading API.
 """
 from __future__ import annotations
 
+import asyncio
 import datetime as dt
 import json
 import math
@@ -1157,7 +1158,7 @@ class PaperTradingEngine:
         # CASH PARKING: buy with idle cash (after all entries)
         # ============================================================
         if self._config.risk.cash_parking_enabled and not parking_sold_today:
-            self._parking_buy(session_id, today)
+            await self._parking_buy(session_id, today)
 
         summary = self._finalize_day(today, session_st, exits, entries, rejected, len(candidate_rows))
         summary["reconciliation"] = recon
@@ -1741,7 +1742,7 @@ class PaperTradingEngine:
         session_cash = max(0.0, session_equity - session_mv)
         return session_equity, session_cash
 
-    def _parking_buy(self, session_id: str, today: dt.date) -> None:
+    async def _parking_buy(self, session_id: str, today: dt.date) -> None:
         """Buy or top-up parking with idle cash after all entries are done."""
         risk = self._config.risk
         parking_st = self._state.get_parking_state(session_id)
@@ -1810,28 +1811,79 @@ class PaperTradingEngine:
         if qty <= 0:
             return
 
-        logger.info("parking_buy", symbol=sym, qty=qty, price=round(price, 2))
+        MAX_ATTEMPTS = 3
+        CONFIRM_SECS = 30
+
+        for attempt in range(1, MAX_ATTEMPTS + 1):
+            if attempt > 1:
+                bars = self._broker.get_latest_bars([sym])
+                if sym not in bars:
+                    return
+                price = bars[sym].close
+                if price <= 0 or investable < price:
+                    return
+                qty = int(investable / price)
+                if qty <= 0:
+                    return
+
+            logger.info("parking_buy", symbol=sym, qty=qty, price=round(price, 2), attempt=attempt)
             try:
                 order = self._broker.submit_market_buy(sym, qty)
-            for _ in range(5):
+            except Exception as e:
-                time.sleep(1)
+                logger.warning("parking_buy_submit_failed", error=str(e), attempt=attempt)
-                filled = self._broker.get_order(order.id)
+                if attempt < MAX_ATTEMPTS:
-                if filled and filled.filled_avg_price:
+                    await asyncio.sleep(5)
-                    avg_price = filled.filled_avg_price
+                continue
+
+            filled_price: float | None = None
+            for _ in range(CONFIRM_SECS):
+                await asyncio.sleep(1)
+                o = self._broker.get_order(order.id)
+                if o and o.filled_avg_price:
+                    filled_price = o.filled_avg_price
+                    break
+
+            if filled_price is None:
+                o = self._broker.get_order(order.id)
+                if o and o.filled_avg_price:
+                    filled_price = o.filled_avg_price
+
+            if filled_price is not None:
                 self._state.save_parking_state(
-                        session_id, sym, today, qty, avg_price, avg_price * qty,
+                    session_id, sym, today, qty, filled_price, filled_price * qty,
-                        peak_price=avg_price, gate_in_sgov=1 if target == "sgov" else 0,
+                    peak_price=filled_price, gate_in_sgov=1 if target == "sgov" else 0,
                     committed_target=target,
                 )
                 self._state.open_trade(
                     session_id, sym, "parking", None,
-                        today.isoformat(), avg_price, qty,
+                    today.isoformat(), filled_price, qty,
                 )
-                    logger.info("parking_filled", symbol=sym, qty=qty, price=round(avg_price, 2))
+                logger.info("parking_filled", symbol=sym, qty=qty, price=round(filled_price, 2))
                 return
-            logger.warning("parking_buy_timeout", symbol=sym, order_id=order.id)
+
-        except Exception as e:
+            logger.warning("parking_buy_timeout", symbol=sym, order_id=order.id, attempt=attempt)
-            logger.warning("parking_buy_failed", error=str(e))
+            try:
+                self._broker.cancel_order(order.id)
+            except Exception:
+                # cancel may fail if order filled between final check and cancel call
+                o = self._broker.get_order(order.id)
+                if o and o.filled_avg_price:
+                    self._state.save_parking_state(
+                        session_id, sym, today, qty, o.filled_avg_price, o.filled_avg_price * qty,
+                        peak_price=o.filled_avg_price, gate_in_sgov=1 if target == "sgov" else 0,
+                        committed_target=target,
+                    )
+                    self._state.open_trade(
+                        session_id, sym, "parking", None,
+                        today.isoformat(), o.filled_avg_price, qty,
+                    )
+                    logger.info("parking_filled_after_cancel_fail", symbol=sym)
+                    return
+
+            if attempt < MAX_ATTEMPTS:
+                await asyncio.sleep(5)
+
+        logger.error("parking_buy_all_attempts_failed", symbol=sym)
 
     # ------------------------------------------------------------------ #
     # Phased execution: reaction_close / next_open / monitor
@@ -2093,7 +2145,7 @@ class PaperTradingEngine:
 
         # CASH PARKING: buy with remaining idle cash after entries
         if self._config.risk.cash_parking_enabled and not parking_sold_today:
-            self._parking_buy(session_id, today)
+            await self._parking_buy(session_id, today)
 
         summary = self._finalize_day(today, session_st, exits, entries, rejected, len(next_open_rows))
         summary["phase"] = phase