SAML SSO and sandbox reliability improvements

Features

• Added SAML SSO authentication support, enabling enterprise single sign-on login flows with configurable attribute resolution.

Fixes

• Hardened the SSO login flow with improved attribute resolution and more robust handling of SAML assertions.
• Fixed sandbox script execution to avoid injecting an implicit return statement when the script already contains one.
• Fixed datasource bindings to correctly unwrap object returns from run_script calls in OpenUI.
• Fixed widget creation to filter agents by team scope and exclude the Admin Agent from the agent selection list.