Update API specifications with fern api update

[github-actions]

Update API specifications by running fern api update.

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Note

Low Risk
Contract-only OpenAPI changes; no runtime code in this diff, though SDK consumers may need to adopt cursor pagination and the new required User field.

Overview
This PR refreshes openapi.json from fern api update, documenting API contract changes for SDK generation and public docs.

Log listing now supports cursor pagination: list endpoints for action logs (including children) and organization logs gain an optional cursor query param, responses include nextCursor, and Fern x-fern-pagination metadata is wired for generated clients. Filter fields startAtId, startAfterId, endAtId, and endBeforeId on ActionLogFilter and OrganizationLogFilter are marked deprecated in favor of cursor-based paging.

Single-log GET operations actionLogFind and organizationLogFind are marked deprecated (deprecated: true and x-fern-availability: deprecated).

User schemas add defaultDomainHandleIds (nullable map of landscape id → default domain handle id) on User, UserPartial, and UserRequired, and require it on the full User type. defaultOrganizationId and landscape id map values gain explicit format: id (and domain handles use short-id).

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