Cataclysm-DDA experimental build 2026-08-13-0108

Add serum 51x-"Landru" (#88273)

* Initial commit

* Edit disadvantages

* Increase bonus

* Adjust bonuses

* Add crash effect

* Add RELOADING_SPEED enchant

* Finish serum work

* Update src/character_ammo.cpp

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

* Add `effect_zero_manip`--needs bugfix to work

* IWYU

* IWYU

* IWYU

* Call appropriate effect

---------

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>