Pain crit treshold

### Testmerges

doesn't matter, happens anyways.

### Round ID

_No response_

### Description of the bug

Pain crit treshold not subsidizing over long periods of time.

### What's the difference with what should have happened?

Pretty sure pain should subsidize much quicker, much much quicker, sometimes if left unattended poor bastard gonna lie there to the end of times!

### How do we reproduce this bug?

1.set someone dead ablaze, leave him in there for a hot minutes, inidiary ob for example
2.let them die
3.revive the poor bastard, observe how they struggle!
...

### Issue Bingo

- [X] Issue could be reproduced at least once
- [X] Issue happened in a recent (less than 7 days ago) round
- [X] Couldn't find an existing issue about this (https://github.com/cmss13-devs/cmss13/issues)

Start by reproducing the reported sequence: set someone ablaze, leave them for several minutes, let them die, and revive them. Investigate the pain-crit behavior around the incendiary OB scenario and compare recovery over time. Done means the pain critical state subsidizes more quickly after revival, including after prolonged unattended burning.

Written by the indexing model from the issue text.