feat: Auditable 트레이트 구현 및 97개 모델 적용

- Auditable 트레이트 신규 생성 (bootAuditable 패턴)
  - creating: created_by/updated_by 자동 채우기
  - updating: updated_by 자동 채우기
  - deleting: deleted_by 채우기 + saveQuietly()
  - created/updated/deleted: audit_logs 자동 기록
- 기존 AuditLogger 패턴과 동일한 try/catch 조용한 실패
- 변경된 필드만 before/after 기록 (updated 이벤트)
- auditExclude 프로퍼티로 모델별 제외 필드 설정 가능
- 제외 대상: Attendance, StockTransaction, TodayIssue 등 고빈도/시스템 모델

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

app/Models/Members/UserRole.php

@@ -4,6 +4,7 @@
 
 use App\Models\Permissions\Role;
 use App\Models\Tenants\Tenant;
+use App\Traits\Auditable;
 use App\Traits\BelongsToTenant;
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\SoftDeletes;
@@ -13,7 +14,7 @@
  */
 class UserRole extends Model
 {
-    use BelongsToTenant, SoftDeletes;
+    use Auditable, BelongsToTenant, SoftDeletes;
 
     protected $fillable = [
         'user_id', 'tenant_id', 'role_id', 'assigned_at',

app/Models/Members/UserTenant.php

@@ -3,6 +3,7 @@
 namespace App\Models\Members;
 
 use App\Models\Tenants\Tenant;
+use App\Traits\Auditable;
 use App\Traits\BelongsToTenant;
 use App\Traits\ModelTrait;
 use Illuminate\Database\Eloquent\Model;
@@ -13,7 +14,7 @@
  */
 class UserTenant extends Model
 {
-    use BelongsToTenant, ModelTrait, SoftDeletes;
+    use Auditable, BelongsToTenant, ModelTrait, SoftDeletes;
 
     protected $fillable = [
         'user_id', 'tenant_id', 'is_active', 'is_default', 'joined_at', 'left_at',