fix: auto-backfill market data on startup + fix trading dedup bug

1. Add backfill-market-data init container to scheduler deployment.
   On vanilla start (< 50 bars in market_snapshots), fetches 90 days
   of daily OHLCV from Polygon directly via asyncpg + httpx.

2. Fix trading engine dedup key placement. Previously the Redis dedup
   key was set BEFORE evaluate_recommendation(), so recs skipped as
   outside_trading_window were permanently deduped and never retried
   when the market opened. Now the dedup key is only set AFTER the
   decision for non-retryable outcomes (act, confidence_too_low, etc).
   outside_trading_window skips are retryable.

services/trading/engine.py

@@ -778,10 +778,6 @@ class TradingEngine:
                             continue
 
                         # --- Buy path ---
-                        # Set dedup key for buys
-                        if self.redis is not None:
-                            await self.redis.set(trading_dedupe_key(rec_id), "1", ex=86400)
-
                         # Check if we already hold this ticker — don't double up
                         try:
                             existing_pos = await self.pool.fetchrow(
@@ -789,6 +785,9 @@ class TradingEngine:
                                 ticker,
                             )
                             if existing_pos:
+                                # Permanent skip — safe to dedup
+                                if self.redis is not None:
+                                    await self.redis.set(trading_dedupe_key(rec_id), "1", ex=86400)
                                 continue
                         except Exception:
                             pass
@@ -864,6 +863,19 @@ class TradingEngine:
                         # Persist decision
                         await self._persist_decision(decision)
 
+                        # Set dedup key only for permanent outcomes (act or
+                        # non-retryable skips).  Do NOT dedup
+                        # outside_trading_window — those should be retried
+                        # when the market opens.
+                        retryable_skips = {"outside_trading_window"}
+                        if decision.skip_reason not in retryable_skips:
+                            if self.redis is not None:
+                                await self.redis.set(
+                                    trading_dedupe_key(rec_id), "1", ex=86400,
+                                )
+                            if rec_id:
+                                self.processed_recommendation_ids.add(rec_id)
+
                     except Exception:
                         logger.exception("Error evaluating recommendation %s", rec.get("recommendation_id", "?"))