适配 UI 分离图片编辑 multipart 接口

将标记图 data URL 解码为 PNG 文件部件。

按 Raw GPT Image 2 新合同发送 prompt、尺寸和输出参数。

保留响应 data[].b64_json 解析与 separation 流程不变。

apps/ai-game-creator-shell/src-tauri/src/ui_editor/commands/separation/workflow.rs

@@ -154,6 +154,15 @@ async fn raw_image_edit(
         .strip_prefix("data:")
         .and_then(|v| v.strip_suffix(";base64"))
         .unwrap_or("image/png");
+    if !mime.eq_ignore_ascii_case("image/png") {
+        return Err("图片分离请求只支持 PNG 标记图".to_string());
+    }
+    let image_bytes = base64::engine::general_purpose::STANDARD
+        .decode(data.trim())
+        .map_err(|error| format!("解码标记图失败：{error}"))?;
+    if image_bytes.is_empty() {
+        return Err("标记图不能为空".to_string());
+    }
     let client = crate::http_client::agc_main_site_client_builder()
         .build()
         .map_err(|e| format!("创建图片编辑客户端失败：{e}"))?;
@@ -161,19 +170,22 @@ async fn raw_image_edit(
         "{}/api/raw/v1/images/edit",
         session.api_base_url.trim_end_matches('/')
     );
-    let body = serde_json::json!({
-        "image": {"data": data, "mimeType": mime},
-        "prompt": prompt,
-        "width": width,
-        "height": height,
-        "output_format": "png",
-        "background": "transparent"
-    });
+    let image_part = reqwest::multipart::Part::bytes(image_bytes)
+        .file_name("image.png")
+        .mime_str("image/png")
+        .map_err(|error| format!("构造图片编辑文件部件失败：{error}"))?;
+    let body = reqwest::multipart::Form::new()
+        .part("image", image_part)
+        .text("prompt", prompt.to_string())
+        .text("width", width.to_string())
+        .text("height", height.to_string())
+        .text("output_format", "png")
+        .text("background", "transparent");
     let response = crate::http_client::with_agc_main_site_marker(
         client
             .post(url)
             .bearer_auth(&session.access_token)
-            .json(&body),
+            .multipart(body),
     )
     .send()
     .await