In #98113, several roachtests were updated to run node decommission without the decommission pre-checks introduced in #91893, using --checks=skip, because the decommissions are either not expected to be completeable or the nodes are already decommissioned. While this is by design, we should add a flag or other mechanism to be able to run the decommission pre-checks and output the decommission readiness (including blocking ranges and errors), without actually stopping the decommission, so that we can validate the output in roachtests even in situations where we are attempting to decommission node(s) that cannot complete decommissioning. As such, we can update the roachtests that decommission with --checks=skip to always run the decommission pre-checks.

Jira issue: CRDB-25104