order_version_mismatch on all sig_types with 0.34.6

[sebamarinovic]

Description:
Getting order_version_mismatch (HTTP 400) when posting any order.

Environment:

• py-clob-client==0.34.6
• Python 3.9, Windows
• chain_id=137 (Polygon mainnet)

Error:
PolyApiException[status_code=400, error_message={'error': 'order_version_mismatch'}]

Tested:

• sig_type=0 (EOA): fails
• sig_type=1 (Proxy): fails
• sig_type=2 (Gnosis): fails
• Market orders (FOK): fails
• Both regular and negRisk markets: fails

Account has confirmed SELL trades via web UI.
API key auth works (GET endpoints return 200).