fix: map JSONL result HTTP errors to SDK errors

[tandede]

Problem

The Python SDK documents that its errors inherit from PaddleOCRAPIError. Most synchronous HTTP paths enforce that contract through the shared response mapper, but HTTPClient.fetch_jsonl() calls requests.Response.raise_for_status() directly.

When a completed job's result URL is expired or object storage returns another non-2xx response, the method therefore leaks a raw requests.HTTPError. Callers catching PaddleOCRAPIError cannot handle that result-download failure consistently, and the behavior also differs from the asynchronous JSONL path.

Fix

Route JSONL result response statuses through the existing _raise_for_response() helper before parsing. This preserves the HTTP status and API message in the SDK's typed APIError, without changing successful JSONL parsing.

The regression test serves a local 404 response with a Result expired message and verifies that fetch_jsonl() raises APIError with both the 404 status and response message.

Validation

• python -m pytest -q tests/api_client — 27 passed
• pre-commit run --files paddleocr/_api_client/_http.py tests/api_client/test_http.py — all hooks passed

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