fix: repair nanobots not working at all on broken limbs

[scarf005]

Purpose of change

• fixes Repair nanobot doesn't work with splinted broken limbs #3786

Describe the solution

1. removed mentions of repair nanobots requiring splints (so its behavior matches with Simplify broken limb mending #3054)
2. extracted is_broken logic into has_broken_limb_penalty. hidden ATM to encourage encap?sulation in future
3. extracted broken_heal logic into heal_adjusted. it takes account of whether limb gets penalty from being broken and not splinted.
4. made repair nanobot logic use heal_adjusted.

Describe alternatives you've considered

• making heal_adjusted the default behavior of character::heal

Testing

in both cases player waited ~6 hours with arms broken and repair nanobots active.

Without Splints

without-splints.mp4

it heals slowly.

With Splints

with-splints.mp4

it heals quickly.

Additional context

• bodypart health logic is getting messier.
• spent 40 minutes figuring out why no changes/breakpoints was made after code changes, only to find out cmake changed emitting files from ./cataclysm-tiles into build/src/cataclysm-tiles
• also hecc, i made the PR on my main branch

[scarf005]

cc @KheirFerrum

[RoyalFox2140]

The chief complaint on discord is that this buff to nanobots is a radical shift in balance. While I disagree with that, I think we need to know the exact math for how the heal rate works with and without fast healer and with varying medical qualities such as high disinfectant. We can't make an informed decision on if a player can walk through all damage without knowing if they currently can.

[KheirFerrum]

Okay, after reading what has been shown, I jumped the gun in the Discord due to anxiety over people touching the code I did, a bit of past issues I've had with code being rapidly merged, and not being able to read it over a computer (laptop's broken again). I was under the impression that the repair nanobots had been working on broken limbs when splinted and that this PR was going to give the full benefit to unsplinted limbs. I can see now that this is not the case, and that it didn't work at all for broken limbs (which is a bug, and should be fixed).

I would still suggest that unsplinted limbs be given lower (or no) bonuses from repair nanobots, as they will rapidly heal broken limbs otherwise (a player without mutations can expect almost all of their broken limb repair progress to be from repair nanobots). I would also suggest that it not be tied into the introduced heal_adjusted function as that accounts for mending modifiers from mutations as well, which essentially doubles up on it for characters with those mutations and reduces the use of repair nanobots as a source of flat healing unaffected by both good and bad modifiers to healing.

Other than that it seems fine, I can't read most of the new code format, but the gist looks right.

The description should note what may alter the healing rate (so just whether it's broken/has been splinted in my suggested version)

[scarf005]

I would also suggest that it not be tied into the introduced heal_adjusted function as that accounts for mending modifiers from mutations as well, which essentially doubles up on it for characters with those mutations and

While I agree with the premise, I chose with this solution as it was simpler to implement. Maybe i should make that function boolean predicate...

[chaosvolt]

Failure unrelated, so functioning should be good to go.

Balance and consistency wise, I would object to this if not for the fact that disabled limbs can heal without being splinted anyway as a result of #3054

Either way, making sure that it can be used to improve disabled limbs is reasonable anyway, whether that take the form of only helping splinted limbs heal or applying to all limb healing.

[scarf005]

yeah, could add nerf for limbs without splints in future PR.