fix(scripts): HTTP 错误带上响应体

raise_for_status 只给一行 URL，而 Label Studio 把真正原因写在响应体里。
批量导入返回 500 时看不到任何线索，排查只能靠猜。

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

tests/test_push_predictions.py

@@ -169,3 +169,11 @@ def test_predictions_endpoint_is_not_paginated():
     methods = [method for method, _, _ in session.requests]
     assert methods == ["GET", "DELETE", "DELETE"]      # 只列一次，删两条
     assert session.requests[1][1] == "http://ls/api/predictions/1/"
+
+
+def test_http_errors_include_the_response_body():
+    """Label Studio 把真正原因写在响应体里，只抛 URL 没法排查。"""
+    session = _TokenSession(statuses=[500], payload={"detail": "boom"})
+    client = _client(session)
+    with pytest.raises(RuntimeError, match="HTTP 500.*boom"):
+        client.request("POST", "/api/projects/39/import/predictions", json=[])