[Feature Request] Saving battery with Kindness mode on: only enable once a day until we get a client

[WofWca]

Is your feature request related to a problem? Please describe.
Currently the Kindness mode requires that the Orbot app is always active. I don't know much about Android, but AFAIK this means that battery consumption will increase quite a lot, even though the app is not actually doing much, because the phone can't go to sleep (if that is not the case, feel free to close the issue).

Describe the Solution You'd Like
What we can do instead of keeping the app always active is to only activate the Snowflake proxy a few times a day, and make it very active in that time period by decreasing the PollInterval parameter (see tladesignz/IPtProxy#58) in such a way that the total amount of requests for a new client per day remains the same, but not spread out over the day, and instead concentrated only during those "active" times.

This way the proxy's usefulness remains the same, but the phone gets some time to sleep, and therefore save battery.

An additional benefit is that it would become less likely that the NAT type is determined incorrectly for the current network, as the NAT check would be performed more often (see tladesignz/IPtProxy#59).

Describe the Alternatives You've Considered
Keep things the way they are.

Additional Context

I don't know whether #1091 is purely due to Kindness mode being active, or if it's some bug that can be fixed separately, but what I propose could still be useful.
But perhaps it makes sense to try to fix that issue first.

And again, I do not know how much battery this can save as I am not really familiar with Android and iOS.