fix(provider): 延长媒体超时并终止超时轮转

将图像和视频的默认 HTTP/轮询超时分别提高到 20 分钟和 30 分钟。媒体任务超时后直接失败，不再重试、切换客户端或标记为 upstream_submission_unknown。OpenAI 图像端点遇到上游明确拒绝 response_format 时自动移除并缓存兼容结论。

验证：go test ./... -count=1；go vet ./...；gofmt；相关 Shell bash -n、ShellCheck 与发布脚本回归测试。

apps/api/internal/clients/volces.go

@@ -52,7 +52,7 @@ func (c VolcesClient) runImage(ctx context.Context, request Request, apiKey stri
 	}
 	resp, err := httpClient(request.HTTPClient, c.HTTPClient).Do(req)
 	if err != nil {
-		return Response{}, &ClientError{Code: "network", Message: err.Error(), Retryable: true}
+		return Response{}, transportClientError(err)
 	}
 	if err := notifyResponseReceived(request); err != nil {
 		return Response{}, err
@@ -199,7 +199,7 @@ func (c VolcesClient) DeleteVideoTask(ctx context.Context, request Request) (map
 	req.Header.Set("Authorization", "Bearer "+apiKey)
 	response, err := httpClient(request.HTTPClient, c.HTTPClient).Do(req)
 	if err != nil {
-		return nil, "", &ClientError{Code: "network", Message: err.Error(), Retryable: true}
+		return nil, "", transportClientError(err)
 	}
 	requestID := requestIDFromHTTPResponse(response)
 	result, err := decodeHTTPResponse(response)
@@ -239,7 +239,7 @@ func (c VolcesClient) postJSON(ctx context.Context, request Request, baseURL str
 	}
 	resp, err := httpClient(request.HTTPClient, c.HTTPClient).Do(req)
 	if err != nil {
-		return nil, "", nil, &ClientError{Code: "network", Message: err.Error(), Retryable: true}
+		return nil, "", nil, transportClientError(err)
 	}
 	if err := notifyResponseReceived(request); err != nil {
 		return nil, "", nil, err
@@ -271,7 +271,7 @@ func (c VolcesClient) getJSON(ctx context.Context, request Request, baseURL stri
 	req.Header.Set("Authorization", "Bearer "+apiKey)
 	resp, err := httpClient(request.HTTPClient, c.HTTPClient).Do(req)
 	if err != nil {
-		return nil, "", nil, &ClientError{Code: "network", Message: err.Error(), Retryable: true}
+		return nil, "", nil, transportClientError(err)
 	}
 	requestID := requestIDFromHTTPResponse(resp)
 	result, wire, err := decodeHTTPResponseForProtocol(resp, ProtocolVolcesContents)
@@ -1184,9 +1184,10 @@ func volcesPollInterval(request Request) time.Duration {
 }
 
 func volcesPollTimeout(request Request) time.Duration {
-	seconds := numericValue(firstPresent(request.Candidate.PlatformConfig["volcesPollTimeoutSeconds"], request.Body["pollTimeoutSeconds"], request.Body["poll_timeout_seconds"]), 600)
+	fallbackSeconds := ProviderRequestTimeout(request.Kind).Seconds()
+	seconds := numericValue(firstPresent(request.Candidate.PlatformConfig["volcesPollTimeoutSeconds"], request.Body["pollTimeoutSeconds"], request.Body["poll_timeout_seconds"]), fallbackSeconds)
 	if seconds < 1 {
-		seconds = 600
+		seconds = fallbackSeconds
 	}
 	return time.Duration(seconds) * time.Second
 }