feat:문서 resolve/upsert API 추가- React 연동용 resolve API (GET /documents/resolve)

- Upsert API (POST /documents/upsert)
- ResolveRequest, UpsertRequest FormRequest 생성
- DocumentService에 resolve/upsert 로직 추가
- document_category common_codes 마이그레이션
- 에러/성공 메시지 i18n 추가

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

routes/api/v1/documents.php

@@ -20,6 +20,10 @@
 
 // 문서 CRUD + 결재
 Route::prefix('documents')->group(function () {
+    // Resolve/Upsert (React 연동용)
+    Route::get('/resolve', [DocumentController::class, 'resolve'])->name('v1.documents.resolve');
+    Route::post('/upsert', [DocumentController::class, 'upsert'])->name('v1.documents.upsert');
+
     // 문서 CRUD
     Route::get('/', [DocumentController::class, 'index'])->name('v1.documents.index');
     Route::get('/{id}', [DocumentController::class, 'show'])->whereNumber('id')->name('v1.documents.show');
@@ -32,4 +36,4 @@
     Route::post('/{id}/approve', [DocumentController::class, 'approve'])->whereNumber('id')->name('v1.documents.approve');
     Route::post('/{id}/reject', [DocumentController::class, 'reject'])->whereNumber('id')->name('v1.documents.reject');
     Route::post('/{id}/cancel', [DocumentController::class, 'cancel'])->whereNumber('id')->name('v1.documents.cancel');
-});
+});