fix(review): persist last_review + correct resolver enrollment key

두 개의 프로덕션 버그 수정 (둘 다 infrastructure/repositories.py):

1. MySQLReviewCardRepository.save_card 가 last_review 를 저장하지 않아
   review_card.last_review 가 항상 NULL 로 남았다. find_review_targets 의
   멱등성 조건(rc.last_review IS NULL OR qs.submitted_at > rc.last_review)이
   항상 참이 되어 야간 배치가 매 실행마다 전 카드를 재리뷰(당일 재리뷰로
   처리 → FSRS stability 왜곡). 실측: 같은 날 재실행 시 skipped=0, updated=453.
   INSERT/UPDATE 에 last_review 추가.

2. MySQLEnrollmentQuizResolver.get_member_id 가 `enrollment WHERE id=%s` 로
   조회했으나 enrollment 테이블 PK 는 enrollment_id 이고 id 컬럼은 없음
   (V1__baseline.sql). "Unknown column 'id'" 로 유사문제 추천 경로 전체가
   실패했다. WHERE enrollment_id=%s 로 수정.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: jongjunn

infrastructure/repositories.py

@@ -317,14 +317,14 @@ def get_card(self, enrollment_id: str, lesson_id: str):
 
     def save_card(self, enrollment_id: str, lesson_id: str, card: Card) -> None:
         sql = """
-            INSERT INTO review_card (enrollment_id, lesson_id, stability, difficulty, due, state)
-            VALUES (%s, %s, %s, %s, %s, %s)
+            INSERT INTO review_card (enrollment_id, lesson_id, stability, difficulty, due, last_review, state)
+            VALUES (%s, %s, %s, %s, %s, %s, %s)
             ON DUPLICATE KEY UPDATE
               stability = VALUES(stability), difficulty = VALUES(difficulty),
-              due = VALUES(due), state = VALUES(state)
+              due = VALUES(due), last_review = VALUES(last_review), state = VALUES(state)
         """
         with get_connection() as conn, conn.cursor() as cur:
-            cur.execute(sql, (enrollment_id, lesson_id, card.stability, card.difficulty, card.due, str(card.state)))
+            cur.execute(sql, (enrollment_id, lesson_id, card.stability, card.difficulty, card.due, card.last_review, str(card.state)))
 
 
 class MySQLPendingReviewRepository:
@@ -430,7 +430,7 @@ class MySQLEnrollmentQuizResolver:
     lesson↔quiz는 N:N(lesson_quiz_map)이라 '이 학생이 그 레슨 퀴즈 중 가장 최근 제출한 quiz'를 택함."""
 
     def get_member_id(self, enrollment_id: str):
-        sql = "SELECT member_id FROM enrollment WHERE id = %s"
+        sql = "SELECT member_id FROM enrollment WHERE enrollment_id = %s"
         with get_connection() as conn, conn.cursor() as cur:
             cur.execute(sql, (enrollment_id,))
             row = cur.fetchone()