修复 requests 2.34+ 移除 ProxyError 导致的登录报错

- requests 2.34+ 已移除 ProxyError 属性
- 代理错误统一为 ConnectionError，通过错误信息判断是否为代理问题
- 代理错误时刷新代理并重试，非代理连接错误也重试

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

core/douyu/login.py

@@ -162,16 +162,27 @@ class DouyuLogin:
                     f"{method.upper()} {safe_url} 超时，耗时 {elapsed:.1f}s，"
                     f"timeout={timeout}"
                 ) from exc
-            except requests.ProxyError as exc:
+            except requests.ConnectionError as exc:
+                # requests 2.34+ 已移除 ProxyError，代理错误统一为 ConnectionError
+                is_proxy_err = "proxy" in str(exc).lower() or "Proxy" in type(exc).__name__
+                if is_proxy_err:
+                    elapsed = time.monotonic() - started
+                    logger.warning(f"代理连接失败，尝试 {attempt + 1}/{max_retries}: {exc}")
+                    if attempt < max_retries - 1:
+                        self._refresh_proxy()
+                        time.sleep(1)
+                        continue
+                    raise ConnectionError(
+                        f"{method.upper()} {safe_url} 代理连接失败，已重试 {max_retries} 次"
+                    ) from exc
+                # 非代理的 ConnectionError 也重试
                 elapsed = time.monotonic() - started
-                logger.warning(f"代理连接失败，尝试 {attempt + 1}/{max_retries}: {exc}")
+                logger.warning(f"连接失败，尝试 {attempt + 1}/{max_retries}: {exc}")
                 if attempt < max_retries - 1:
-                    # 刷新代理
-                    self._refresh_proxy()
                     time.sleep(1)
                     continue
                 raise ConnectionError(
-                    f"{method.upper()} {safe_url} 代理连接失败，已重试 {max_retries} 次"
+                    f"{method.upper()} {safe_url} 连接失败，已重试 {max_retries} 次"
                 ) from exc
             except requests.RequestException as exc:
                 elapsed = time.monotonic() - started