feat(balance): House solar odds lowered from 33% per home to 15%

[RoyalFox2140]

Checklist

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Purpose of change

Solar roofs go from 8, to 9, to 16 panels on residential homes. They're also very common. I think dialing it back should be okay, houses are something you spend all game securing and looting.

Describe the solution

The odds were at a distribution with 30 odds of nothing, and 5 odds for 8, 9, and 16 panels respectively. This is 11% chance per solar odd, and a total of 33% for any solar. I think this is too high.

I've set a 15% chance for solar panels, at 2% odds for 16 panels, 8% for 8 panels, and 5% for 9 panels. This is still a significantly large amount as 8 panels is amazing to find. at 15% chance per house you're generally going to find one house in a neighborhood of 10 homes that has these panels. Whereas before every third house would have solar statistically (For each home which calls this nested mapgen specifically)

Describe alternatives you've considered

A lot of other stuff. Let's just take a small and easy approach.

Testing

They still do spawn.

Additional context

That's it until we get more data, and until I can steal Chaos for power balancing.

[chaosvolt]

Simple enough. Reducing the total number of panels to something like 2x2, 2x3, and 2x4 could be an acceptable alternative too.