Constant MAX_COORDINATED_COMMIT_PAYLOAD_BYTES 

pub const MAX_COORDINATED_COMMIT_PAYLOAD_BYTES: usize = _; // 16_777_216usize

Fixed control-plane bound for one connector’s coordinated-commit payload.

Connectors must keep prepared metadata at or below this limit before returning it to the checkpoint runtime. Bulk records belong in the sink’s data plane, referenced by the bounded payload.