feat(tkfb): 연차 데이터 정본 전환 — vacation_balance_details → sp_vacation_balances

대시보드 + 연간 연차 현황 페이지의 읽기를 tksupport 정본 테이블로 전환.
- dashboardModel: getVacationBalance worker_id → user_id, sp_vacation_balances
- dashboardController: worker_id 전달 제거, user_id 직접 사용
- vacationBalanceModel: 읽기 함수 3개 sp_vacation_balances로 전환
  (쓰기 함수 deductByPriority 등은 vacation_balance_details 유지)
- remaining_days: STORED GENERATED 대신 (total_days - used_days) AS 계산

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

system1-factory/api/models/dashboardModel.js

@@ -27,17 +27,19 @@ const DashboardModel = {
   /**
    * 연차 현황 조회 (쿼리 2)
    */
-  getVacationBalance: async (workerId, year) => {
-    if (!workerId) return [];
+  getVacationBalance: async (userId, year) => {
+    if (!userId) return [];
     const db = await getDb();
     const [rows] = await db.execute(`
-      SELECT vbd.vacation_type_id, vbd.total_days, vbd.used_days, vbd.remaining_days,
+      SELECT svb.vacation_type_id, svb.total_days, svb.used_days,
+             (svb.total_days - svb.used_days) AS remaining_days,
+             svb.balance_type, svb.expires_at,
              vt.type_name, vt.type_code
-      FROM vacation_balance_details vbd
-      JOIN vacation_types vt ON vbd.vacation_type_id = vt.id
-      WHERE vbd.worker_id = ? AND vbd.year = ?
+      FROM sp_vacation_balances svb
+      JOIN vacation_types vt ON svb.vacation_type_id = vt.id
+      WHERE svb.user_id = ? AND svb.year = ?
       ORDER BY vt.priority
-    `, [workerId, year]);
+    `, [userId, year]);
     return rows;
   },