feat: I-8 휴가 정책 관리 API 구현

- LeavePolicyController: 휴가 정책 CRUD API
- LeavePolicyService: 정책 관리 로직
- LeavePolicy 모델: 다중 테넌트 지원
- FormRequest 검증 클래스
- Swagger 문서화
- leave_policies 테이블 마이그레이션

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/Http/Requests/LeavePolicy/UpdateRequest.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace App\Http\Requests\LeavePolicy;
+
+use App\Models\Tenants\LeavePolicy;
+use Illuminate\Foundation\Http\FormRequest;
+use Illuminate\Validation\Rule;
+
+class UpdateRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    public function rules(): array
+    {
+        return [
+            'standard_type' => ['sometimes', Rule::in(LeavePolicy::STANDARD_TYPES)],
+            'fiscal_start_month' => ['sometimes', 'integer', 'min:1', 'max:12'],
+            'fiscal_start_day' => ['sometimes', 'integer', 'min:1', 'max:31'],
+            'default_annual_leave' => ['sometimes', 'integer', 'min:0', 'max:100'],
+            'additional_leave_per_year' => ['sometimes', 'integer', 'min:0', 'max:10'],
+            'max_annual_leave' => ['sometimes', 'integer', 'min:0', 'max:100'],
+            'carry_over_enabled' => ['sometimes', 'boolean'],
+            'carry_over_max_days' => ['sometimes', 'integer', 'min:0', 'max:100'],
+            'carry_over_expiry_months' => ['sometimes', 'integer', 'min:0', 'max:24'],
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            'standard_type.in' => __('validation.in', ['attribute' => '기준 유형']),
+            'fiscal_start_month.min' => __('validation.min.numeric', ['attribute' => '기준월', 'min' => 1]),
+            'fiscal_start_month.max' => __('validation.max.numeric', ['attribute' => '기준월', 'max' => 12]),
+            'fiscal_start_day.min' => __('validation.min.numeric', ['attribute' => '기준일', 'min' => 1]),
+            'fiscal_start_day.max' => __('validation.max.numeric', ['attribute' => '기준일', 'max' => 31]),
+        ];
+    }
+}