* Instead of calling RandAddSeedSleep anytime the scheduler goes idle, call its replacement (RandAddSeedPeriodic) just once per minute. This has better guarantees of actually being run, and helps limit how frequently the dynamic env data is gathered. * Since this code runs once per minute regardless now, we no longer need to keep track of the last time strengthening was run; just do it always. * Make strengthening time context dependent (100 ms at startup, 10 ms once per minute afterwards).
Partial backport of core PR17270: