fix(http客户端): 增强超时错误处理并保留URL用于错误提示

在请求发送和响应体读取时添加明确的超时错误处理，使用clone保留URL以便在错误信息中显示

backend/src/middlewares/http_client.rs

@@ -49,7 +49,8 @@ pub async fn execute_http(req: HttpRequest, opts: HttpClientOptions) -> Result<H
     let client = builder.build()?;
 
     // Build request
-    let mut rb = client.request(req.method.parse()?, req.url);
+    // 使用 clone 保留 url 以便在错误提示中引用
+    let mut rb = client.request(req.method.parse()?, req.url.clone());
 
     // Also set per-request timeout to ensure it takes effect in all cases
     if let Some(ms) = opts.timeout_ms {
@@ -85,7 +86,20 @@ pub async fn execute_http(req: HttpRequest, opts: HttpClientOptions) -> Result<H
         rb = rb.json(&b);
     }
 
-    let resp = rb.send().await?;
+    // 发送请求，明确标注超时错误
+    let resp = match rb.send().await {
+        Ok(r) => r,
+        Err(e) => {
+            if e.is_timeout() {
+                let hint = match opts.timeout_ms {
+                    Some(ms) => format!("http timeout: request {} timed out after {}ms", req.url, ms),
+                    None => format!("http timeout: request {} timed out", req.url),
+                };
+                return Err(anyhow::Error::new(e).context(hint));
+            }
+            return Err(e.into());
+        }
+    };
     let status = resp.status().as_u16();
     let headers_out: Map<String, Value> = resp
         .headers()
@@ -93,7 +107,20 @@ pub async fn execute_http(req: HttpRequest, opts: HttpClientOptions) -> Result<H
         .map(|(k, v)| (k.to_string(), Value::String(v.to_str().unwrap_or("").to_string())))
         .collect();
 
-    let text = resp.text().await?;
+    // 读取响应体，明确标注超时错误
+    let text = match resp.text().await {
+        Ok(t) => t,
+        Err(e) => {
+            if e.is_timeout() {
+                let hint = match opts.timeout_ms {
+                    Some(ms) => format!("http timeout: reading body from {} timed out after {}ms", req.url, ms),
+                    None => format!("http timeout: reading body from {} timed out", req.url),
+                };
+                return Err(anyhow::Error::new(e).context(hint));
+            }
+            return Err(e.into());
+        }
+    };
     let parsed_body: Value = serde_json::from_str(&text).unwrap_or_else(|_| Value::String(text));
 
     Ok(HttpResponse {