Without health assessment, lastHealthy can point to a render that was never applied

Behavior#

Without spec.healthAssessment, the rollout verdict is always Healthy. convoy sets status.lastHealthy to the render of each attempt. This includes a render that the dry run or the apply rejected, and that convoy never stored.

Effect#

If you add a failurePolicy later, a rollback can target a render that never ran and is not in the render store. The rollback then holds without an apply, as in KB-1.

Workaround#

Set spec.healthAssessment on Releases that can later get a failurePolicy.

Fix direction#

Advance status.lastHealthy only for a render that convoy applied.