feat: sam_stat P1 도메인 확장 (Phase 3)

- 차원 테이블: dim_client, dim_product 마이그레이션 + SCD Type 2 동기화 (DimensionSyncService)
- 재고 통계: stat_inventory_daily + InventoryStatService (stocks, stock_transactions, inspections)
- 견적/영업 통계: stat_quote_pipeline_daily + QuoteStatService (quotes, biddings, sales_prospects)
- 인사/근태 통계: stat_hr_attendance_daily + HrStatService (attendances, leaves, user_tenants)
- KPI/알림: stat_kpi_targets, stat_alerts + KpiAlertService + StatCheckKpiAlertsCommand
- StatAggregatorService에 inventory, quote, hr 도메인 추가 (총 6개 도메인)
- 스케줄러: stat:check-kpi-alerts 매일 09:00 등록

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

app/Services/Stats/InventoryStatService.php

@@ -0,0 +1,97 @@
+<?php
+
+namespace App\Services\Stats;
+
+use App\Models\Stats\Daily\StatInventoryDaily;
+use Carbon\Carbon;
+use Illuminate\Support\Facades\DB;
+
+class InventoryStatService implements StatDomainServiceInterface
+{
+    public function aggregateDaily(int $tenantId, Carbon $date): int
+    {
+        $dateStr = $date->format('Y-m-d');
+
+        // 재고 현황 (stocks 테이블 - 현재 스냅샷)
+        $stockSummary = DB::connection('mysql')
+            ->table('stocks')
+            ->where('tenant_id', $tenantId)
+            ->whereNull('deleted_at')
+            ->selectRaw('
+                COUNT(*) as sku_count,
+                COALESCE(SUM(stock_qty), 0) as total_qty,
+                SUM(CASE WHEN stock_qty < safety_stock AND safety_stock > 0 THEN 1 ELSE 0 END) as below_safety,
+                SUM(CASE WHEN stock_qty = 0 THEN 1 ELSE 0 END) as zero_stock,
+                SUM(CASE WHEN stock_qty > safety_stock * 3 AND safety_stock > 0 THEN 1 ELSE 0 END) as excess_stock
+            ')
+            ->first();
+
+        // 입고 (stock_transactions type = 'receipt')
+        $receiptStats = DB::connection('mysql')
+            ->table('stock_transactions')
+            ->where('tenant_id', $tenantId)
+            ->whereDate('created_at', $dateStr)
+            ->where('type', 'receipt')
+            ->selectRaw('COUNT(*) as cnt, COALESCE(SUM(qty), 0) as total_qty')
+            ->first();
+
+        // 출고 (stock_transactions type = 'issue')
+        $issueStats = DB::connection('mysql')
+            ->table('stock_transactions')
+            ->where('tenant_id', $tenantId)
+            ->whereDate('created_at', $dateStr)
+            ->where('type', 'issue')
+            ->selectRaw('COUNT(*) as cnt, COALESCE(SUM(ABS(qty)), 0) as total_qty')
+            ->first();
+
+        // 품질검사 (inspections)
+        $inspectionStats = DB::connection('mysql')
+            ->table('inspections')
+            ->where('tenant_id', $tenantId)
+            ->where('inspection_date', $dateStr)
+            ->whereNull('deleted_at')
+            ->selectRaw("
+                COUNT(*) as cnt,
+                SUM(CASE WHEN result = 'pass' THEN 1 ELSE 0 END) as pass_count,
+                SUM(CASE WHEN result = 'fail' THEN 1 ELSE 0 END) as fail_count
+            ")
+            ->first();
+
+        $inspectionCount = $inspectionStats->cnt ?? 0;
+        $passCount = $inspectionStats->pass_count ?? 0;
+        $failCount = $inspectionStats->fail_count ?? 0;
+        $passRate = $inspectionCount > 0 ? ($passCount / $inspectionCount) * 100 : 0;
+
+        StatInventoryDaily::updateOrCreate(
+            ['tenant_id' => $tenantId, 'stat_date' => $dateStr],
+            [
+                'total_sku_count' => $stockSummary->sku_count ?? 0,
+                'total_stock_qty' => $stockSummary->total_qty ?? 0,
+                'total_stock_value' => 0, // 단가 정보 없어 Phase 4에서 보완
+                'receipt_count' => $receiptStats->cnt ?? 0,
+                'receipt_qty' => $receiptStats->total_qty ?? 0,
+                'receipt_amount' => 0,
+                'issue_count' => $issueStats->cnt ?? 0,
+                'issue_qty' => $issueStats->total_qty ?? 0,
+                'issue_amount' => 0,
+                'below_safety_count' => $stockSummary->below_safety ?? 0,
+                'zero_stock_count' => $stockSummary->zero_stock ?? 0,
+                'excess_stock_count' => $stockSummary->excess_stock ?? 0,
+                'inspection_count' => $inspectionCount,
+                'inspection_pass_count' => $passCount,
+                'inspection_fail_count' => $failCount,
+                'inspection_pass_rate' => $passRate,
+                'turnover_rate' => 0, // 월간 집계에서 계산
+            ]
+        );
+
+        return 1;
+    }
+
+    public function aggregateMonthly(int $tenantId, int $year, int $month): int
+    {
+        // 재고 도메인은 일간 스냅샷 기반이므로 별도 월간 테이블 없음
+        // 필요시 Phase 4에서 stat_inventory_monthly 추가
+        return 0;
+    }
+}