feat: 대시보드 API 및 FCM 푸시 알림 API 구현

Dashboard API:
- DashboardController, DashboardService 추가
- /dashboard/summary, /charts, /approvals 엔드포인트

Push Notification API:
- FCM 토큰 관리 (등록/해제/목록)
- 알림 설정 관리 (유형별 on/off, 알림음 설정)
- 알림 유형: deposit, withdrawal, order, approval, attendance, notice, system
- 알림음: default, deposit, withdrawal, order, approval, urgent
- PushDeviceToken, PushNotificationSetting 모델
- Swagger 문서 추가

app/Http/Controllers/Api/V1/DashboardController.php

@@ -0,0 +1,47 @@
+<?php
+
+namespace App\Http\Controllers\Api\V1;
+
+use App\Http\Controllers\Controller;
+use App\Http\Requests\V1\Dashboard\DashboardApprovalsRequest;
+use App\Http\Requests\V1\Dashboard\DashboardChartsRequest;
+use App\Http\Responses\ApiResponse;
+use App\Services\DashboardService;
+use Illuminate\Http\JsonResponse;
+
+class DashboardController extends Controller
+{
+    public function __construct(
+        private readonly DashboardService $dashboardService
+    ) {}
+
+    /**
+     * 대시보드 요약 데이터 조회
+     */
+    public function summary(): JsonResponse
+    {
+        $data = $this->dashboardService->summary();
+
+        return ApiResponse::handle(['data' => $data], __('message.fetched'));
+    }
+
+    /**
+     * 대시보드 차트 데이터 조회
+     */
+    public function charts(DashboardChartsRequest $request): JsonResponse
+    {
+        $data = $this->dashboardService->charts($request->validated());
+
+        return ApiResponse::handle(['data' => $data], __('message.fetched'));
+    }
+
+    /**
+     * 결재 현황 조회
+     */
+    public function approvals(DashboardApprovalsRequest $request): JsonResponse
+    {
+        $data = $this->dashboardService->approvals($request->validated());
+
+        return ApiResponse::handle(['data' => $data], __('message.fetched'));
+    }
+}