Fix flashback cardset legality and rewards timestamp handling

- Add 2018 Promos (14) and 2022 Promos (4) to flashback mode legal cardsets
- Convert Unix timestamps to datetime in rewards POST/PATCH for PostgreSQL

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/db_engine.py

@@ -69,9 +69,9 @@ CARDSETS = {
     },
     "hall-of-fame": {"primary": [x for x in range(1, 30)], "human": ranked_cardsets},
     "flashback": {
-        "primary": [13, 5, 1, 3, 8],  # 2018, 2019, 2021, 2022, Mario
+        "primary": [13, 14, 5, 1, 3, 4, 8],  # 2018 + Promos, 2019, 2021, 2022 + Promos, Mario
         "secondary": [24],  # 2025
-        "human": [13, 5, 1, 3, 8],  # 2018, 2019, 2021, 2022
+        "human": [13, 14, 5, 1, 3, 4, 8],  # 2018 + Promos, 2019, 2021, 2022 + Promos
     },
     "gauntlet-3": {
         "primary": [13],  # 2018

app/routers_v2/rewards.py

@@ -112,7 +112,11 @@ async def post_rewards(reward: RewardModel, token: str = Depends(oauth2_scheme))
             detail='You are not authorized to post rewards. This event has been logged.'
         )
 
-    this_reward = Reward(**reward.dict())
+    reward_data = reward.dict()
+    # Convert milliseconds timestamp to datetime for PostgreSQL
+    if reward_data.get('created'):
+        reward_data['created'] = datetime.fromtimestamp(reward_data['created'] / 1000)
+    this_reward = Reward(**reward_data)
 
     saved = this_reward.save()
     if saved == 1:
@@ -148,7 +152,8 @@ async def patch_reward(
     if team_id is not None:
         this_reward.team_id = team_id
     if created is not None:
-        this_reward.created = created
+        # Convert milliseconds timestamp to datetime for PostgreSQL
+        this_reward.created = datetime.fromtimestamp(created / 1000)
 
     if this_reward.save() == 1:
         return_val = model_to_dict(this_reward)