Align to the new knowledge search route for reliability

To ensure consistent behavior across releases, the knowledge search endpoint has been renamed from search_vectors to search_knowledge. Update clients to avoid failures against the deprecated route.

Details

• Breaking change requiring client updates to the new route
• Terminology aligns with the Knowledge model and documentation
• No schema changes; only the endpoint name is affected

Who this is for: Any team using Knowledge search in production or CI/CD automation.