feat(character-gallery): 이미지 구매 기능 추가

SodaLive/Sources/Chat/Character/Detail/Gallery/CharacterDetailGalleryRepository.swift

@@ -40,4 +40,8 @@ final class CharacterDetailGalleryRepository {
             )
         )
     }
+    
+    func purchaseCharacterImage(imageId: Int) -> AnyPublisher<Response, MoyaError> {
+        return characterApi.requestPublisher(.purchaseCharacterImage(imageId: imageId))
+    }
 }

SodaLive/Sources/Chat/Character/Detail/Gallery/CharacterDetailGalleryViewModel.swift

@@ -73,14 +73,65 @@ final class CharacterDetailGalleryViewModel: ObservableObject {
             isShowImageViewer = true
         } else {
             // 미소유 이미지 - 구매 다이얼로그 표시
+            selectedImageIndex = index
             isShowPurchaseDialog = true
         }
     }
     
     func onPurchaseConfirm() {
-        // TODO: 구매 API 연동 구현 예정
-        print("구매 확인: \(selectedItem?.id ?? 0)")
         isShowPurchaseDialog = false
+        if isLoading {
+            return
+        }
+        
+        if let imageItem = selectedItem {
+            isLoading = true
+            repository.purchaseCharacterImage(imageId: imageItem.id)
+                .sink { result in
+                    switch result {
+                    case .finished:
+                        DEBUG_LOG("finish")
+                    case .failure(let error):
+                        ERROR_LOG(error.localizedDescription)
+                    }
+                } receiveValue: { [unowned self] response in
+                    let responseData = response.data
+                    self.isLoading = false
+                    
+                    do {
+                        let jsonDecoder = JSONDecoder()
+                        let decoded = try jsonDecoder.decode(ApiResponse<CharacterImagePurchaseResponse>.self, from: responseData)
+                        
+                        if let data = decoded.data, decoded.success {
+                            var copyGalleryItems = self.galleryItems
+                            copyGalleryItems[self.selectedImageIndex].imageUrl = data.imageUrl
+                            copyGalleryItems[self.selectedImageIndex].isOwned = true
+                            self.galleryItems = copyGalleryItems
+                            self.ownedCount += 1
+                        } else {
+                            if let message = decoded.message {
+                                self.errorMessage = message
+                            } else {
+                                self.errorMessage = "다시 시도해 주세요.\n계속 같은 문제가 발생할 경우 고객센터로 문의 주시기 바랍니다."
+                            }
+                            
+                            self.isShowPopup = true
+                        }
+                        
+                        self.selectedImageIndex = 0
+                        self.selectedItem = nil
+                    } catch {
+                        self.selectedImageIndex = 0
+                        self.selectedItem = nil
+                        ERROR_LOG(String(describing: error))
+                        self.errorMessage = "다시 시도해 주세요.\n계속 같은 문제가 발생할 경우 고객센터로 문의 주시기 바랍니다."
+                        self.isShowPopup = true
+                    }
+                }
+                .store(in: &subscription)
+        } else {
+            isShowPurchaseDialog = false
+        }
     }
     
     func onPurchaseCancel() {

SodaLive/Sources/Chat/Character/Detail/Gallery/CharacterImageListResponse.swift

@@ -13,7 +13,7 @@ struct CharacterImageListResponse: Decodable {
 
 struct CharacterImageListItemResponse: Decodable, Hashable {
     let id: Int
-    let imageUrl: String
-    let isOwned: Bool
+    var imageUrl: String
+    var isOwned: Bool
     let imagePriceCan: Int
 }

SodaLive/Sources/Chat/Character/Detail/Gallery/CharacterImagePurchaseRequest.swift

@@ -0,0 +1,11 @@
+//
+//  CharacterImagePurchaseRequest.swift
+//  SodaLive
+//
+//  Created by klaus on 9/5/25.
+//
+
+struct CharacterImagePurchaseRequest: Encodable {
+    let imageId: Int
+    let container: String = "ios"
+}

SodaLive/Sources/Chat/Character/Detail/Gallery/CharacterImagePurchaseResponse.swift

@@ -0,0 +1,10 @@
+//
+//  CharacterImagePurchaseResponse.swift
+//  SodaLive
+//
+//  Created by klaus on 9/5/25.
+//
+
+struct CharacterImagePurchaseResponse: Decodable {
+    let imageUrl: String
+}