Fix Python vector search authentication

[SWORDIntel]

Summary

• align the Python ctypes vector query layout with the native qihse_vector_query_t ABI
• initialize and retain the process-local SDK user required by authorization-aware search
• attach that user to every Python vector query
• add a regression test covering authenticated native vector search

Root cause

The native query struct gained a required user field, but the Python ctypes definition was not updated. Native search read beyond the shorter Python struct, producing EACCES or invalid pointers in isolated worker processes.

Validation

• PYTHONPATH=python python3 -m pytest -q python/tests/test_vector_search_auth.py python/tests/test_recall.py
• FRAMEWERX QIHSE wrapper suite: 23 passed
• git diff --check