Late joiners get extra exhaustion if day time based resets are enabled

[MonzUn]

If a user joins on a day before the reset time, they will be awarded time both for joining on that day and for resetting on that day, potentially ending up with more exhaustion that what should be possible for the time that has passed.

Repro steps

1. Configure the server to reset at a specific time, for example at 19:00.
2. Configure the server to give different amounts of exhaustion on different days, for example 3 hours on Friday and 6 hours on Saturday.
3. Start the server.
4. Have one user join on Friday after reset time. This should give them 3 hours of exhaustion
5. Wait until Saturday (Or any debug method you have for pretending it's another weekday)
6. Have another user join on Saturday before reset time. This will give them 6 hours of exhaustion.
7. Wait until reset time.
8. Observe that the user who joined on Saturday will now have 12 hours of exhaustion while the user who joined on Friday only has 9.

[JulianMa]

This is not limited to newly joining users, but this affects all users:
The code which retro-awards exaustion time for previous days (daysSinceLastRefresh >= 1d) has a bug, which lets to double-awarding the exhaustion time of the last day.
I wrote a Unit-Test to trigger this specific bug, see my fork.
The Test TryRefresh_MultiDayGap_DoubleCountsFridayAllotment is triggering the bug,
the parameterized test TryRefresh_VaryingGap_CorrectRemaining is good at showing were it all goes wrong :)

https://github.com/JulianMa/Eco/blob/feature/exhaustion-monitor-repro-unit-test/Server/Eco.Tests/Players/ExhaustionMonitorTests.cs