[Bombastic Perks] Add overwriting perkchain support

[Standing-Storm]

Summary

Mods "[Bombastic Perks] Add overwriting perkchain support"

Purpose of change

I wanted to add additional +1 stat perks to Bombastic Perks but not clutter up the mutation menu, but since the basic engine used u_add_trait there was no way to do that. However, swapping it over to u_mutate_towards should keep all basic behavior the same while allowing perks later in chains to overwrite perks earlier in chains, so that (for example) Stronger becomes Even Stronger and +1 STR becomes +2, rather than simply having Even Stronger give you another +1 and having both in your menu simultaneously.

Describe the solution

Change u_add_trait to u_mutate_towards. Add additional +1 stat perks that overwrite the previous perks in their chain, allowing +2 to all stats (at the cost of 8 perk points).

Describe alternatives you've considered

Testing

Previous perks are properly selectable, new perks in the chain are not selectable unless previous perks are taken, previous perks in the chain cannot be selected a second time after taking the later perks, and part 2 of the chain properly overwrites part 1:

Additional context

This should also allow adding otherwise-unselectable starting traits as perks, since u_mutate_towards respects the cancels field.

[github-actions]

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• You HAVE been doing cardio. +2 Dexterity.

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[ashGlaw]

Good idea, and better infrastructure for future changes

[github-actions]

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