Review round on the pivoted design:
- node-24 (static) kept an unconditional hosted pnpm cache restore while the
coverage and consumers lanes skip it under failover. On the self-hosted VM
that restore downloads ~180 MB into /home/runner, a path pnpm never reads
there, adding latency and contention during an outage. Gate it with the same
`vars.DSH_CI_FAILOVER != 'selfhosted'` condition so all three lanes match.
- Runbook switch step 2 said "Re-run failed jobs", but the documented
indefinite-queue outage leaves jobs queued (not failed), which cannot be
re-run in place and do not retarget on variable change. Correct both language
sides to cancel the run and re-run all jobs, or push a new commit.
- The standby-lane comment still described the switch as a one-line runs-on
change; it is now setting the admin-only DSH_CI_FAILOVER variable.