Explosion subsystem (#17499)

* Initial port

* pause air

* decoupled input from processing

* explosion condition tweak

* closer to original recursive code

* accurate explosions

* better defer calls

* glob fix

* fix

* DON'T DO THAT

* initial deferral code

* small explosions ignored

* lower thresholds

* better thresholds again

* forbid powernet defer during init, explosions too

* don't block your own network regen

* use procs

* better thresholds, always defer at least

* admin notice

* subsytem updated

* Allow removal from networks

* defer till rebuild

* dir

* Update breaker_box.dm

* no init means no init

* then flag it...

---------

Co-authored-by: Selis <12716288+ItsSelis@users.noreply.github.com>
Co-authored-by: C.L. <killer65311@gmail.com>
Co-authored-by: Kashargul <144968721+Kashargul@users.noreply.github.com>

code/controllers/configuration/entries/general.dm

@@ -472,9 +472,6 @@
 ///datum/config_entry/number/simultaneous_pm_warning_timeout
 //	default = 100
 
-/// Defines whether the server uses recursive or circular explosions.
-/datum/config_entry/flag/use_recursive_explosions
-
 /// Multiplier for how much weaker explosions are on neighboring z levels.
 /datum/config_entry/number/multi_z_explosion_scalar
 	default = 0.5