fix(ai): 修正挑品清單銷售日期查詢

services/ai_product_pick_agent.py

@@ -76,12 +76,12 @@ def _fetch_candidates(conn, limit: int) -> List[Dict[str, Any]]:
             LEFT JOIN (
                 SELECT
                     "商品ID" AS sku,
-                    SUM(CASE WHEN snapshot_date >= CURRENT_DATE - 7
+                    SUM(CASE WHEN snapshot_date::date >= CURRENT_DATE - 7
                              THEN COALESCE("銷售金額"::numeric, 0) ELSE 0 END) AS sales_7d,
-                    SUM(CASE WHEN snapshot_date >= CURRENT_DATE - 14
-                              AND snapshot_date < CURRENT_DATE - 7
+                    SUM(CASE WHEN snapshot_date::date >= CURRENT_DATE - 14
+                              AND snapshot_date::date < CURRENT_DATE - 7
                              THEN COALESCE("銷售金額"::numeric, 0) ELSE 0 END) AS sales_prev_7d,
-                    SUM(CASE WHEN snapshot_date >= CURRENT_DATE - 7
+                    SUM(CASE WHEN snapshot_date::date >= CURRENT_DATE - 7
                              THEN COALESCE("數量"::numeric, 0) ELSE 0 END) AS qty_7d
                 FROM daily_sales_snapshot
                 GROUP BY "商品ID"
@@ -157,6 +157,10 @@ def _fetch_candidates(conn, limit: int) -> List[Dict[str, Any]]:
         return [dict(row) for row in conn.execute(sql, {"limit": max(limit * 6, 100)}).mappings().all()]
     except Exception as exc:
         logger.warning("[ProductPickAgent] sales-aware query failed, fallback without sales: %s", exc)
+        try:
+            conn.rollback()
+        except Exception:
+            pass
         fallback = text("""
             WITH latest_momo AS (
                 SELECT
@@ -315,8 +319,10 @@ def _write_pick(conn, pick: Dict[str, Any]) -> None:
 def generate_product_pick_list(engine, limit: int = 30) -> ProductPickResult:
     """產生並保存 AI 建議挑品清單。"""
     generated_at = datetime.now().isoformat(timespec="seconds")
-    with engine.begin() as conn:
+    with engine.connect() as conn:
         rows = _fetch_candidates(conn, limit)
+
+    with engine.begin() as conn:
         scored = [_score_candidate(row) for row in rows if _to_float(row.get("pchome_price")) > 0]
         picks = [
             pick for pick in scored