feat: [재무] 어음 V8 + 상품권 접대비 연동 + 일반전표/계정과목 API

- Bill 확장 필드 (V8), Loan 상품권 카테고리/접대비 자동 연동
- GeneralJournalEntry CRUD, AccountSubject API
- 접대비/복리후생비 날짜 필터, 매출채권 soft delete 제외
- 바로빌 연동 API 엔드포인트 추가
- 부가세 상세 조회 API

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/Models/Tenants/JournalEntry.php

@@ -0,0 +1,53 @@
+<?php
+
+namespace App\Models\Tenants;
+
+use App\Traits\BelongsToTenant;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\HasMany;
+use Illuminate\Database\Eloquent\SoftDeletes;
+
+class JournalEntry extends Model
+{
+    use BelongsToTenant, SoftDeletes;
+
+    protected $fillable = [
+        'tenant_id',
+        'entry_no',
+        'entry_date',
+        'entry_type',
+        'description',
+        'total_debit',
+        'total_credit',
+        'status',
+        'source_type',
+        'source_key',
+        'created_by_name',
+        'attachment_note',
+    ];
+
+    protected $casts = [
+        'entry_date' => 'date',
+        'total_debit' => 'integer',
+        'total_credit' => 'integer',
+    ];
+
+    // Status
+    public const STATUS_DRAFT = 'draft';
+    public const STATUS_CONFIRMED = 'confirmed';
+
+    // Source type
+    public const SOURCE_MANUAL = 'manual';
+    public const SOURCE_BANK_TRANSACTION = 'bank_transaction';
+
+    // Entry type
+    public const TYPE_GENERAL = 'general';
+
+    /**
+     * 분개 행 관계
+     */
+    public function lines(): HasMany
+    {
+        return $this->hasMany(JournalEntryLine::class)->orderBy('line_no');
+    }
+}