* chore: only retry when retry-able
* chore: revert dbg change
* refactor: per review
* fix: check for available frontend first
* docs: more explain&longer timeout&feat: more retry at every level&try send select 1
* fix: use `sql` method for "SELECT 1"
* fix: also put recover flows in spawned task and a dead loop
* test: update transient error in flow rebuild test
* chore: sleep after sqlness sleep
* chore: add a warning
* chore: wait even more time after reboot