Revert "Remove test for old chmod behavior during staging"

This reverts commit eada723d142e2a8bbcd34d5bf367d415fdb7747b.
Revert "Do not chmod app bits since CC is doing that now"

This reverts commit c91e59350ab865ec74114c435fd20638cffdd297.
Only cancel health_check when transitioning from STARTING to CRASHED

[#79882732]
Always register routes through nats on an interval

* Validate the value of the interval (greater than equal to 0)
* Up router registration interval to 20 seconds (up from 5)

[#80010862]
Change the starting state to crash when loading instance-snapshot