The cast to 'T' in run_curl_into was redundant: mypy already narrows
the return value of json.loads() to type T after the isinstance(ret,
expected_type) check (where expected_type: type[T]).
Remove the unnecessary cast and clean up the unused 'cast' import.
This satisfies the new warn_redundant_casts mypy rule.
Assisted-by: unsloth/Qwen3.6-35B-A3B-GGUF:IQ4_NL and pi.dev 0.81.1
Signed-off-by: Jan Lindemann <jan@janware.com>