dpkg inconsistent state after interrupted apt full-upgrade on Kali rolling

Kali Linux follows a Debian-based rolling release model where the supported upgrade path is apt update followed by apt full-upgrade. An interrupted upgrade can leave the package database in an inconsistent state and the kernel and initramfs partially updated.

Safe recovery is constrained by the need for a stable boot with a writable root filesystem, intact package lists, and network access to fetch missing packages. The distribution advises against partial upgrades and mixing Kali repositories with Debian stable/testing or third-party repositories.

There is no built-in distribution-managed snapshot or automatic rollback for a failed kali-linux-core or toolchain upgrade. The decision to provide or rely on external rollback tools such as Timeshift or btrfs snapshots remains unresolved and is left to the administrator. Live USB sessions cannot persist package repairs to installed media.

What conditions define when a Kali system is considered recoverable in place versus requiring repair from external media? Is there a documented distribution stance on using external snapshot tools for kali-linux-core or toolchain upgrades? How should repository consistency be verified before attempting package database repair?