[BOOK-379] feat: 노트 수정 화면에서 빈값 -> 내용 추가, 내용 -> 빈값으로 바꾸는 동작 정상 처리

Author: doyeonk429

src/Projects/BKPresentation/Sources/MainFlow/Note/ViewModel/NoteForm.swift

@@ -6,7 +6,7 @@ struct NoteForm: Equatable {
     let page: Int
     let sentence: String
     let emotion: Emotion
-    let appreciation: String
+    let appreciation: String?
 }
 
 extension NoteForm {

src/Projects/BKPresentation/Sources/MainFlow/NoteEdit/View/NoteEditView.swift

@@ -248,7 +248,12 @@ final class NoteEditView: BaseView {
 
         pageField.setText("\(recordInfo.pageNumber)")
         sentenceTextView.setText(recordInfo.quote)
-        appreciationTextView.setText(recordInfo.review)
+        
+        if let review = recordInfo.review {
+            appreciationTextView.setText(review)
+        } else {
+            
+        }
 
         // 감정 라벨은 selectedEmotion 바인딩에서만 설정
     }

src/Projects/BKPresentation/Sources/MainFlow/NoteEdit/ViewModel/NoteEditViewModel.swift

@@ -23,7 +23,7 @@ final class NoteEditViewModel: BaseViewModel {
         case errorHandled
         case presentEmotionEdit
         case emotionSelected(Emotion)
-        case saveButtonTapped(formData: (page: Int?, sentence: String, appreciation: String))
+        case saveButtonTapped(formData: (page: Int?, sentence: String, appreciation: String?))
         case patchRecordSuccessed(RecordInfo)
         case deleteButtonTapped
         case deleteRecordSuccessed
@@ -95,9 +95,8 @@ final class NoteEditViewModel: BaseViewModel {
         case .saveButtonTapped(let formData):
             guard let selectedEmotion = state.selectedEmotion,
                   let page = formData.page,
-                  !formData.sentence.isEmpty,
-                  !formData.appreciation.isEmpty else { 
-                break 
+                  !formData.sentence.isEmpty else {
+                break
             }
 
             let noteForm = NoteForm(