feat: 근태관리/직원관리 API 구현

- AttendanceController, AttendanceService 추가
- EmployeeController, EmployeeService 추가
- Attendance 모델 및 마이그레이션 추가
- TenantUserProfile에 employee_status 컬럼 추가
- DepartmentService 트리 조회 기능 개선
- Swagger 문서 추가 (AttendanceApi, EmployeeApi)
- API 라우트 등록

app/Http/Requests/Employee/IndexRequest.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace App\Http\Requests\Employee;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class IndexRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    public function rules(): array
+    {
+        return [
+            'q' => 'nullable|string|max:100',
+            'status' => 'nullable|in:active,leave,resigned',
+            'department_id' => 'nullable|integer|min:1',
+            'has_account' => 'nullable|in:0,1,true,false',
+            'sort_by' => 'nullable|in:created_at,name,employee_status,department_id',
+            'sort_dir' => 'nullable|in:asc,desc',
+            'page' => 'nullable|integer|min:1',
+            'per_page' => 'nullable|integer|min:1|max:100',
+        ];
+    }
+}