fix(requests): fall back to stdlib json in Response.json() when kwargs are passed (#639)

[apoorvdarshan]

Fixes #639

Root cause

Response.json(**kw) forwards its keyword arguments straight to loads():

return loads(self.content, **kw)

In curl_cffi/requests/models.py, loads is bound to orjson.loads when orjson is installed and to json.loads otherwise. orjson.loads() accepts no keyword arguments, whereas the stdlib json.loads() does. A call such as response.json(parse_float=Decimal) therefore raises TypeError only when orjson is installed.

Fix

Keep the faster orjson.loads for the common no-kwargs case, but fall back to the stdlib json.loads whenever the caller passes keyword arguments. The no-kwargs fast path is unchanged.

Tests

Added test_json_kwargs_with_orjson, which verifies that r.json(parse_float=Decimal) returns a Decimal when orjson is installed.

• The regression test fails on unmodified code with TypeError.
• The regression test and surrounding JSON/redirect tests pass with this fix.
• ruff check and ruff format --check are clean on the changed files.

Review checklist

• I have manually reviewed the changes and fully understand the code.

Disclosure: prepared with AI assistance; manually reviewed and verified locally.