feat(tksupport): Sprint 001 Section C — 전사 휴가관리 구현

- 전사 휴가 부여/관리 (company-holidays) CRUD + 연차차감 트랜잭션
- 전체 휴가관리 대시보드 (vacation-dashboard) 부서별/직원별 현황
- 내 휴가 현황 개선 (/my-status) balance_type별 카드, 전사 휴가일
- requireSupportTeam 미들웨어, 부서명 JOIN, 마이그레이션 002 추가
- 사이드바 roles 기반 메뉴 필터링 (하위호환 유지)

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

tksupport/api/models/vacationDashboardModel.js

@@ -0,0 +1,55 @@
+const { getPool } = require('../middleware/auth');
+
+const vacationDashboardModel = {
+  async getSummary(year) {
+    const db = getPool();
+    const [rows] = await db.query(`
+      SELECT
+        d.department_id, COALESCE(d.department_name, '미배정') as department_name,
+        COUNT(DISTINCT su.user_id) as employee_count,
+        AVG(vb.total_days - vb.used_days) as avg_remaining,
+        SUM(CASE WHEN (vb.total_days - vb.used_days) <= 2 THEN 1 ELSE 0 END) as low_balance_count
+      FROM sso_users su
+      LEFT JOIN departments d ON su.department_id = d.department_id
+      LEFT JOIN sp_vacation_balances vb ON su.user_id = vb.user_id
+        AND vb.year = ? AND vb.balance_type = 'AUTO'
+      WHERE su.is_active = 1
+      GROUP BY d.department_id
+    `, [year]);
+    return rows;
+  },
+
+  async getEmployeeList(year, filters = {}) {
+    const db = getPool();
+    let query = `
+      SELECT su.user_id, su.name, su.username, su.hire_date, su.department_id,
+        COALESCE(d.department_name, '미배정') as department_name,
+        vb.id, vb.balance_type, vb.total_days, vb.used_days,
+        (vb.total_days - vb.used_days) as remaining_days,
+        vb.expires_at, vt.type_name, vt.type_code
+      FROM sso_users su
+      LEFT JOIN departments d ON su.department_id = d.department_id
+      LEFT JOIN sp_vacation_balances vb ON su.user_id = vb.user_id
+        AND (vb.year = ? OR (vb.balance_type = 'LONG_SERVICE' AND vb.expires_at IS NULL))
+      LEFT JOIN vacation_types vt ON vb.vacation_type_id = vt.id
+      WHERE su.is_active = 1
+    `;
+    const params = [year];
+
+    if (filters.department_id) {
+      query += ' AND su.department_id = ?';
+      params.push(filters.department_id);
+    }
+    if (filters.search_name) {
+      query += ' AND su.name LIKE ?';
+      params.push(`%${filters.search_name}%`);
+    }
+
+    query += ' ORDER BY su.name ASC';
+
+    const [rows] = await db.query(query, params);
+    return rows;
+  }
+};
+
+module.exports = vacationDashboardModel;