fix: add 24h sell cooldown to prevent immediate re-entry after profit-taking

After selling a position (profit-taking, stop-loss, or recommendation),
the engine would immediately buy it back on the next poll cycle if a
buy recommendation existed. Now sets a 24h Redis cooldown key per ticker
on any sell, and checks it before entering a new buy position.

services/trading/engine.py

@@ -32,6 +32,7 @@ except ImportError:
 from services.shared.config import TradingConfig
 from services.shared.redis_keys import (
     QUEUE_BROKER,
+    TRADING_DEDUPE_PREFIX,
     queue_key,
     trading_dedupe_key,
 )
@@ -735,6 +736,9 @@ class TradingEngine:
                             if self.redis is not None:
                                 broker_queue = queue_key(QUEUE_BROKER)
                                 await self.redis.rpush(broker_queue, json.dumps(order_job))
+                                # Set 24h cooldown to prevent immediate re-entry
+                                cooldown_key = f"{TRADING_DEDUPE_PREFIX}:sell_cooldown:{ticker}"
+                                await self.redis.set(cooldown_key, "1", ex=86400)
                                 logger.info(
                                     "Pushed sell order for %s (%d shares, ~$%.2f) to broker queue",
                                     ticker, sell_qty, estimated_proceeds,
@@ -779,6 +783,16 @@ class TradingEngine:
                             continue
 
                         # --- Buy path ---
+                        # Check sell cooldown — don't re-enter a position we just sold
+                        if self.redis is not None:
+                            cooldown_key = f"{TRADING_DEDUPE_PREFIX}:sell_cooldown:{ticker}"
+                            if await self.redis.get(cooldown_key):
+                                logger.info(
+                                    "Decision for %s: skip (reason=sell_cooldown)",
+                                    ticker,
+                                )
+                                continue
+
                         # Check if we already hold this ticker — don't double up
                         try:
                             existing_pos = await self.pool.fetchrow(
@@ -1852,6 +1866,9 @@ class TradingEngine:
             try:
                 broker_queue = queue_key(QUEUE_BROKER)
                 await self.redis.rpush(broker_queue, json.dumps(order_job))
+                # Set 24h cooldown to prevent immediate re-entry
+                cooldown_key = f"{TRADING_DEDUPE_PREFIX}:sell_cooldown:{ticker}"
+                await self.redis.set(cooldown_key, "1", ex=86400)
                 logger.info("Submitted sell order for %s (%d shares): %s", ticker, quantity, reason)
             except Exception:
                 logger.exception("Failed to push sell order for %s", ticker)