feat(tkuser): Sprint 001 Section A — 연차/휴가 백엔드 전환 (DB + API)

workers/vacation_balance_details → sso_users/sp_vacation_balances 기반 전환.
부서장 설정, 승인권한 CRUD, vacation_settings 테이블, 장기근속 자동부여,
startup migration 추가.

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

user-management/api/controllers/vacationSettingsController.js

@@ -0,0 +1,27 @@
+/**
+ * Vacation Settings Controller
+ *
+ * 연차 계산 규칙 설정 GET/PUT
+ */
+
+const vacationSettingsModel = require('../models/vacationSettingsModel');
+
+async function getSettings(req, res, next) {
+  try {
+    const data = await vacationSettingsModel.getAll();
+    res.json({ success: true, data });
+  } catch (err) { next(err); }
+}
+
+async function updateSettings(req, res, next) {
+  try {
+    const { settings } = req.body;
+    if (!settings || !Array.isArray(settings)) {
+      return res.status(400).json({ success: false, error: 'settings 배열이 필요합니다' });
+    }
+    const data = await vacationSettingsModel.updateSettings(settings, req.user.user_id);
+    res.json({ success: true, data, message: '설정이 업데이트되었습니다' });
+  } catch (err) { next(err); }
+}
+
+module.exports = { getSettings, updateSettings };