Constant WAL_OBJECT_RESERVATION_PARTITION 

pub const WAL_OBJECT_RESERVATION_PARTITION: i32 = i32::MIN; // -2_147_483_648i32

Reserved delete-floor partition used to protect an uploaded object until its range records are committed.

Its key/value remain readable by 1.x brokers: older readers project it as floor zero on a negative partition, which no data partition can address.