Steps to reproduce:
List the minimal actions needed to reproduce the behaviour.

1. run the following plugin

def process_writes(influxdb3_local, table_batches, args=None):
    allowed = {"info", "warn", "error", "query", "write", "cache"}
    attrs = {name for name in dir(influxdb3_local) if not name.startswith("__")}
    extras = attrs - allowed
    missing = allowed - attrs
    if extras or missing:
        raise RuntimeError(f"unexpected attributes: extras={sorted(extras)}, missing={sorted(missing)}")

Expected behaviour:
PyPluginCallApi should only expose Python methods info, warn, error, query, write, and cache, so the regression test should pass.

Actual behaviour:
The test fails with RuntimeError: unexpected attributes: extras=['log_args_to_string', 'write_to_db'], missing=[], showing that internal helpers were exported to Python.