ref(builder/registry): have builder push slugrunner in ExecStartPost
fix(controller): add retries on container creation
fix(controller): work around fleet state reporting bug
where units report as "failed" before they go "active"
fix(controller): add retry on destroy
Merge pull request #2072 from gabrtv/retry

Retry Fleet container scheduling operations
Merge pull request #2062 from gabrtv/seed-registry

ref(builder/registry): have builder push slugrunner in ExecStartPost