🧪 Add test for check_error

[rnovatorov]

🎯 What: The testing gap addressed
The enapter.http.api.errors.check_error function and the associated Error and MultiError classes lacked comprehensive unit testing to verify their expected behaviors under different HTTP response conditions.

📊 Coverage: What scenarios are now tested

1. Happy Path: Returns without exception when response.is_success is True.
2. Generic/Non-JSON Error Path: Properly delegates to response.raise_for_status() when a non-success response doesn't contain a JSON payload.
3. Single API Error: Correctly raises a singular Error with parsed message, code, and details when the API returns an error DTO with exactly one error.
4. Multiple API Errors: Correctly aggregates and raises a MultiError when the API returns an error DTO with a list of errors.
5. Error DTO Parsing Edge Cases: Tests empty payload fields and lists to ensure exceptions are raised logically or fallbacks (<no message>) are used.

✨ Result: The improvement in test coverage
src/enapter/http/api/errors.py is now rigorously tested, improving confidence when parsing various shapes of HTTP errors from the Enapter API. Tested the functionality using pytest-asyncio and httpx.Response mocks properly equipped with request properties.

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PR created automatically by Jules for task 3453424892746361646 started by @rnovatorov

[google-labs-jules]

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[rnovatorov]

Thx @jules, nice PR! Could you test that check_error reads the response body? This is important for streamed responses.

[google-labs-jules]

Thx @jules, nice PR! Could you test that check_error reads the response body? This is important for streamed responses.

Added a new unit test, test_check_error_reads_body, to mock and assert that response.aread() is called properly when checking errors! This verifies the response body is always consumed for streamed requests.