feat: 管理台直接对部员加义工时（必填原因，独立多条记录）

- schema.sql + db/index.ts 迁移：hours 表移除 UNIQUE(activity_id,user_id)
  约束，改由 id 自增主键唯一定位；启动时检测到旧结构会自动
  RENAME+重建表+INSERT 搬迁历史数据；外部 FK pragma 仍生效
- hours.ts batch 接口：为兼容去掉 UNIQUE 后的行为等价，改成
  『先 DELETE 旧行 + 再 INSERT 新行』，同人同活动仍为一行覆盖语义
- 新增 POST /hours/direct-add：
  · items = [{user_id, hours, reason}]，每条记录前置校验（uid 存在、
    hours>0、reason 非空），错误以分号拼接返回
  · 首次调用自动创建活动「【补录】直接加义工时长」（start/end
    2024-01-01 ~ 2099-12-31）作为虚拟承载活动，后续复用
  · 全事务 INSERT，每次加时独立写入多行（不合并）
  · 响应：{ ok, added, total_hours, results:[{class,name,...}], direct_add_activity_id }
- api/index.ts hoursApi.directAdd：新增带完整返回类型签名的 TS 封装
- Users.tsx 双入口：
  · 工具栏：选中部员后与『批量删除』并列，出现『批量加义工时(N)』
    主按钮 → 打开共用 Modal 一次加多人
  · 部员详情弹窗：「累计时长」卡片独立加『加义工时』小按钮，
    点后复用同一表单只为当前人录 1 条
- 共用 Direct Add Modal：
  · 顶部说明卡（每条原因独立保存；挂在【补录】活动；勾选人名 chip 列表）
  · 时长输入：number，min=0.1 step=0.1，前端校验 >0
  · 原因输入：textarea 必填，标红字星号，字数计数，提交前 trim 非空校验
  · 提交 loading 锁按钮；成功 toast 显示前 5 人名字 + 总人数 + 总小时；
    然后 load() 刷新列表累计时长列，若详情弹窗开着自动重新拉详情

server/src/db/index.ts

@@ -136,6 +136,47 @@ export async function initDb() {
     }
   } catch (e) { console.error('User_groups migration error', e); }
 
+  try {
+    const hoursExists = d.prepareCompat(`SELECT name FROM sqlite_master WHERE type='table' AND name='hours'`).get();
+    if (hoursExists) {
+      const uniqueIdx = d.prepareCompat(`
+        SELECT name, sql FROM sqlite_master
+         WHERE type='index' AND tbl_name='hours' AND (unique=1 OR sql LIKE '%UNIQUE%')
+      `).all();
+      const tblSql = (d.prepareCompat(`SELECT sql FROM sqlite_master WHERE type='table' AND name='hours'`).get() as any)?.sql || '';
+      const hasOldUnique = uniqueIdx.length > 0 || tblSql.includes('UNIQUE(activity_id, user_id)');
+      if (hasOldUnique) {
+        console.log('[DB] Migrating hours: drop UNIQUE(activity_id,user_id) constraint, allow multiple rows per activity+user');
+        d.execCompat('BEGIN');
+        d.execCompat(`CREATE TABLE IF NOT EXISTS hours_new (
+          id INTEGER PRIMARY KEY AUTOINCREMENT,
+          activity_id INTEGER NOT NULL,
+          user_id INTEGER NOT NULL,
+          hours REAL NOT NULL DEFAULT 0,
+          remark TEXT,
+          created_at TEXT NOT NULL DEFAULT (datetime('now','+8 hours')),
+          FOREIGN KEY (activity_id) REFERENCES activities(id) ON DELETE CASCADE,
+          FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
+        )`);
+        d.execCompat(`
+          INSERT INTO hours_new (id, activity_id, user_id, hours, remark, created_at)
+          SELECT id, activity_id, user_id, hours, remark, created_at FROM hours
+        `);
+        for (const idx of uniqueIdx) {
+          try { d.execCompat(`DROP INDEX IF EXISTS "${idx.name}"`); } catch {}
+        }
+        d.execCompat('DROP TABLE IF EXISTS hours');
+        d.execCompat('ALTER TABLE hours_new RENAME TO hours');
+        d.execCompat('COMMIT');
+        d.save();
+        console.log('[DB] hours UNIQUE constraint migration done');
+      }
+    }
+  } catch (e: any) {
+    console.error('Hours migration error', e);
+    try { d.execCompat('ROLLBACK'); } catch {}
+  }
+
   const adminCount = d.prepareCompat('SELECT COUNT(*) as c FROM admins').get();
   if (!adminCount || adminCount.c === 0) {
     const hash = bcrypt.hashSync('admin123', 10);

server/src/db/schema.sql

@@ -46,8 +46,7 @@ CREATE TABLE IF NOT EXISTS hours (
   remark TEXT,
   created_at TEXT NOT NULL DEFAULT (datetime('now','+8 hours')),
   FOREIGN KEY (activity_id) REFERENCES activities(id) ON DELETE CASCADE,
-  FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE,
-  UNIQUE(activity_id, user_id)
+  FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
 );
 
 CREATE TABLE IF NOT EXISTS admins (

server/src/routes/hours.ts

@@ -12,19 +12,19 @@ router.post('/batch', authMiddleware, (req: AuthRequest, res: Response) => {
   const db = getDb();
   try {
     db.execCompat('BEGIN');
-    const upsert = db.prepareCompat(`
+    const delOld = db.prepareCompat('DELETE FROM hours WHERE activity_id = ? AND user_id = ?');
+    const insertNew = db.prepareCompat(`
       INSERT INTO hours (activity_id, user_id, hours, remark)
       VALUES (?,?,?,?)
-      ON CONFLICT(activity_id, user_id) DO UPDATE SET hours=excluded.hours, remark=excluded.remark
     `);
-    const delZero = db.prepareCompat('DELETE FROM hours WHERE activity_id = ? AND user_id = ? AND hours = 0 AND (remark IS NULL OR remark = \'\')');
     for (const it of items) {
       const h = Number(it.hours) || 0;
       const r = (it.remark ?? '').toString();
       if (h === 0 && !r) {
-        delZero.run(activity_id, it.user_id);
+        delOld.run(activity_id, it.user_id);
       } else {
-        upsert.run(activity_id, it.user_id, h, r);
+        delOld.run(activity_id, it.user_id);
+        insertNew.run(activity_id, it.user_id, h, r);
       }
     }
     db.execCompat('COMMIT');
@@ -36,6 +36,77 @@ router.post('/batch', authMiddleware, (req: AuthRequest, res: Response) => {
   }
 });
 
+const DIRECT_ADD_TITLE = '【补录】直接加义工时长';
+
+router.post('/direct-add', authMiddleware, (req: AuthRequest, res: Response) => {
+  const { items } = req.body || {};
+  if (!Array.isArray(items) || items.length === 0) {
+    return res.status(400).json({ error: '请至少选择一名部员' });
+  }
+  const db = getDb();
+  try {
+    const errors: string[] = [];
+    const clean: Array<{ uid: number; user: any; hours: number; reason: string }> = [];
+    for (const it of items) {
+      const uid = Number(it?.user_id);
+      const h = Number(it?.hours);
+      const reason = String(it?.reason ?? '').trim();
+      if (!uid) { errors.push(`无效部员：${JSON.stringify(it)}`); continue; }
+      const user = db.prepareCompat('SELECT id, class, name, volunteer_no FROM users WHERE id = ?').get(uid);
+      if (!user) { errors.push(`部员不存在：${uid}`); continue; }
+      if (!Number.isFinite(h) || h <= 0) {
+        errors.push(`${user.class} ${user.name} 的时长必须大于 0`);
+        continue;
+      }
+      if (!reason) {
+        errors.push(`${user.class} ${user.name} 必须填写原因`);
+        continue;
+      }
+      clean.push({ uid, user, hours: h, reason });
+    }
+    if (errors.length > 0) {
+      return res.status(400).json({ error: errors.join('；') });
+    }
+    db.execCompat('BEGIN');
+    let act = db.prepareCompat('SELECT * FROM activities WHERE title = ?').get(DIRECT_ADD_TITLE) as any;
+    if (!act) {
+      db.prepareCompat(`
+        INSERT INTO activities (title, content, start_time, end_time)
+        VALUES (?, ?, ?, ?)
+      `).run(DIRECT_ADD_TITLE, '管理台直接补录义工时长，不绑定真实活动', '2024-01-01 00:00', '2099-12-31 23:59');
+      act = db.prepareCompat('SELECT * FROM activities WHERE title = ?').get(DIRECT_ADD_TITLE) as any;
+    }
+    const insert = db.prepareCompat(`
+      INSERT INTO hours (activity_id, user_id, hours, remark)
+      VALUES (?,?,?,?)
+    `);
+    const results: any[] = [];
+    for (const c of clean) {
+      insert.run(act.id, c.uid, c.hours, c.reason);
+      results.push({
+        user_id: c.uid,
+        class: c.user.class,
+        name: c.user.name,
+        volunteer_no: c.user.volunteer_no || null,
+        hours: c.hours,
+        reason: c.reason,
+      });
+    }
+    db.execCompat('COMMIT');
+    db.save();
+    res.json({
+      ok: true,
+      added: results.length,
+      total_hours: results.reduce((s, r) => s + r.hours, 0),
+      results,
+      direct_add_activity_id: act.id,
+    });
+  } catch (e: any) {
+    try { db.execCompat('ROLLBACK'); } catch {}
+    res.status(500).json({ error: e.message });
+  }
+});
+
 router.get('/activity/:id', (req: Request, res: Response) => {
   const id = Number(req.params.id);
   const db = getDb();