Toddle parent rostering, Audit Logs for team changes, and API reliability fixes

Over the past couple of weeks we've added Toddle parent and agent rostering, expanded Audit Logs to more team operations, and shipped a round of API and LMS/SIS reliability fixes.

API Updates

• Audit Logs: Creating or updating a team, inviting or adding a member, and updating or deleting a payment method now emit audit events.
• Rate limits: When an upstream provider returns 429, Edlink now forwards the Retry-After header.
• Sources: Creating a duplicate OIDC or SAML source returns 409 instead of a 500. Invalid OIDC configuration URLs and SAML metadata return 400.
• Sharing rules: Creating a rule with an invalid type, target, or state returns 400 instead of a 500.

Pipeline Updates

• Toddle: People ingest parents, with parent–student agent relationships. See Toddle functionality.
• Google: Invalid or already-exchanged authorization codes return 400 during source create instead of a 500.
• Infinite Campus: Staff are marked active when any employment assignment is active for the current school year.
• FACTS: Teachers who were previously students at the district are no longer marked inactive.
• Schoolbox: Invalid or revoked access tokens fail source validation with a clear error instead of a generic request failure.