feat(api): 模型接入 - 统一出网 User-Agent 并支持添加时测试模型

Fixes #39

web/src/services/api/image.ts

@@ -817,12 +817,7 @@ export async function requestGeneration(config: AiConfig, prompt: string, option
               };
         const responseData = isVolcengineArk
             ? await postVolcengineArkImage(requestConfig, payload, options)
-            : (
-                  await axios.post<ImageApiResponse>(aiApiUrl(requestConfig, "/images/generations"), payload, {
-                      headers: aiHeaders(requestConfig, "application/json"),
-                      signal: options?.signal,
-                  })
-              ).data;
+            : await postChannelJSON<ImageApiResponse>(requestConfig, aiApiUrl(requestConfig, "/images/generations"), payload, options);
         const images = parseImagePayload(responseData);
         return images;
     } catch (error) {
@@ -830,6 +825,17 @@ export async function requestGeneration(config: AiConfig, prompt: string, option
     }
 }
 
+async function postChannelJSON<T>(config: ReturnType<typeof resolveModelRequestConfig>, upstreamUrl: string, body: unknown, options?: RequestOptions) {
+    const request = channelRequest(config, upstreamUrl, aiHeaders(config, "application/json"));
+    return (
+        await axios.post<T>(request.url, body, {
+            headers: request.headers,
+            withCredentials: request.credentials === "include",
+            signal: options?.signal,
+        })
+    ).data;
+}
+
 export async function requestEdit(config: AiConfig, prompt: string, references: ReferenceImage[], mask?: ReferenceImage, options?: RequestOptions) {
     const selectedModel = config.model || config.imageModel;
     const requestConfig = resolveModelRequestConfig(config, selectedModel);