fix(loyalty): normalize card id field, fix terminal redeem bug

The terminal redeem failed with "card not found: unknown" because
CardLookupResponse used card_id while CardDetailResponse (from
refreshCard) used id. After refresh, selectedCard.card_id was
undefined.

Fix: standardize on 'id' everywhere (the universal convention):
- CardLookupResponse: card_id → id
- _build_card_lookup_response: card_id= → id=
- loyalty-terminal.js: selectedCard.card_id → selectedCard.id (5 refs)
- Removed the card_id/model_validator approach as unnecessary

Also fixes Chart.js recursion error on analytics page (inline CDN
script instead of optional-libs.html include which caused infinite
template recursion in test context).

342 tests pass.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/modules/loyalty/routes/api/store.py

@@ -420,7 +420,7 @@ def _build_card_lookup_response(card, db=None) -> CardLookupResponse:
             available_rewards.append(reward)
 
     return CardLookupResponse(
-        card_id=card.id,
+        id=card.id,
         card_number=card.card_number,
         customer_id=card.customer_id,
         customer_name=card.customer.full_name if card.customer else None,