feat(API): 입금/출금 알림 Observer 추가 및 LoanController 수정

- DepositIssueObserver, WithdrawalIssueObserver 신규 추가
- TodayIssueObserverService에 입금/출금 핸들러 및 디버그 로그 추가
- TodayIssue 모델에 입금/출금 상수 추가
- AppServiceProvider에 Observer 등록
- ApprovalService에 기존 결재선 사용 시 수동 알림 트리거 추가
- LoanController ApiResponse::handle() → ApiResponse::success() 수정

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

app/Services/TodayIssueObserverService.php

@@ -8,9 +8,11 @@
 use App\Models\Orders\Order;
 use App\Models\PushDeviceToken;
 use App\Models\Tenants\ApprovalStep;
+use App\Models\Tenants\Deposit;
 use App\Models\Tenants\ExpectedExpense;
 use App\Models\Tenants\Stock;
 use App\Models\Tenants\TodayIssue;
+use App\Models\Tenants\Withdrawal;
 use App\Services\Fcm\FcmSender;
 use Carbon\Carbon;
 use Illuminate\Support\Facades\Log;
@@ -261,6 +263,92 @@ public function handleClientDeleted(Client $client): void
         TodayIssue::removeBySource($client->tenant_id, TodayIssue::SOURCE_CLIENT, $client->id);
     }
 
+    /**
+     * 입금 등록 이슈 생성
+     */
+    public function handleDepositCreated(Deposit $deposit): void
+    {
+        Log::info('TodayIssue: Deposit created detected', [
+            'deposit_id' => $deposit->id,
+            'tenant_id' => $deposit->tenant_id,
+            'amount' => $deposit->amount,
+        ]);
+
+        $clientName = $deposit->display_client_name ?: __('message.today_issue.unknown_client');
+        $amount = number_format($deposit->amount ?? 0);
+
+        Log::info('TodayIssue: Creating deposit issue', [
+            'deposit_id' => $deposit->id,
+            'client' => $clientName,
+            'amount' => $amount,
+        ]);
+
+        $this->createIssueWithFcm(
+            tenantId: $deposit->tenant_id,
+            sourceType: TodayIssue::SOURCE_DEPOSIT,
+            sourceId: $deposit->id,
+            badge: TodayIssue::BADGE_DEPOSIT,
+            content: __('message.today_issue.deposit_registered', [
+                'client' => $clientName,
+                'amount' => $amount,
+            ]),
+            path: '/accounting/deposit-management',
+            needsApproval: false,
+            expiresAt: Carbon::now()->addDays(7)
+        );
+    }
+
+    /**
+     * 입금 삭제 시 이슈 삭제
+     */
+    public function handleDepositDeleted(Deposit $deposit): void
+    {
+        TodayIssue::removeBySource($deposit->tenant_id, TodayIssue::SOURCE_DEPOSIT, $deposit->id);
+    }
+
+    /**
+     * 출금 등록 이슈 생성
+     */
+    public function handleWithdrawalCreated(Withdrawal $withdrawal): void
+    {
+        Log::info('TodayIssue: Withdrawal created detected', [
+            'withdrawal_id' => $withdrawal->id,
+            'tenant_id' => $withdrawal->tenant_id,
+            'amount' => $withdrawal->amount,
+        ]);
+
+        $clientName = $withdrawal->display_client_name ?: $withdrawal->merchant_name ?: __('message.today_issue.unknown_client');
+        $amount = number_format($withdrawal->amount ?? 0);
+
+        Log::info('TodayIssue: Creating withdrawal issue', [
+            'withdrawal_id' => $withdrawal->id,
+            'client' => $clientName,
+            'amount' => $amount,
+        ]);
+
+        $this->createIssueWithFcm(
+            tenantId: $withdrawal->tenant_id,
+            sourceType: TodayIssue::SOURCE_WITHDRAWAL,
+            sourceId: $withdrawal->id,
+            badge: TodayIssue::BADGE_WITHDRAWAL,
+            content: __('message.today_issue.withdrawal_registered', [
+                'client' => $clientName,
+                'amount' => $amount,
+            ]),
+            path: '/accounting/withdrawal-management',
+            needsApproval: false,
+            expiresAt: Carbon::now()->addDays(7)
+        );
+    }
+
+    /**
+     * 출금 삭제 시 이슈 삭제
+     */
+    public function handleWithdrawalDeleted(Withdrawal $withdrawal): void
+    {
+        TodayIssue::removeBySource($withdrawal->tenant_id, TodayIssue::SOURCE_WITHDRAWAL, $withdrawal->id);
+    }
+
     /**
      * 세금 신고 이슈 업데이트 (스케줄러에서 호출)
      * 이 메서드는 일일 스케줄러에서 호출하여 세금 신고 이슈를 업데이트합니다.