GHSA-PVXX-R596-F5QJ PraisonAI: `--api-key` flag on `praisonai serve` is not properly enforced

Summary praisonai serve agents and praisonai serve unified both accept --api-key for authentication. The flag is parsed but never wired into the FastAPI app — no middleware, no header check, nothing. The server runs wide open regardless of what key you set. Tested on 4.6.50 from PyPI. Affected...