Fixes exploit allowing players to open Bag of Holding rifts in the Heretic dimension (#85330)

## About The Pull Request

This PR prevents players from opening a BoH tear in the Heretic
dimension areas. It also introduces a new area flag, "NO_BOH", which can
be added to areas to replicate this behavior.

## Why It's Good For The Game

This prevents the (very unlikely) edge case that someone manages to open
a BoH tear in one of the funny hand rooms, which is bad not only because
it fucks over anyone else who gets sacrificed, but could also interfere
with other things on that z-level (shuttles, other Lazy Template areas,
etc).

Messing with some new code here, so if there's better ways to handle
this, by all means, chime in. This is a much more elegant method than
just banning anything but the station.
## Changelog
🆑 Vekter
fix: Fixes an exploit that allowed players to open a Bag of Holding rift
in the Heretic dimension.
/🆑

---------

Co-authored-by: Kapu1178 <75460809+Kapu1178@users.noreply.github.com>

code/__DEFINES/_flags.dm

@@ -136,6 +136,8 @@ GLOBAL_LIST_INIT(bitflags, list(1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 204
 #define VIRTUAL_SAFE_AREA (1<<16)
 /// This area does not allow the Binary channel
 #define BINARY_JAMMING (1<<17)
+/// This area prevents Bag of Holding rifts from being opened.
+#define NO_BOH (1<<18)
 
 /*
 	These defines are used specifically with the atom/pass_flags bitmask

code/_globalvars/bitfields.dm

@@ -64,6 +64,7 @@ DEFINE_BITFIELD(area_flags, list(
 	"UNIQUE_AREA" = UNIQUE_AREA,
 	"VALID_TERRITORY" = VALID_TERRITORY,
 	"XENOBIOLOGY_COMPATIBLE" = XENOBIOLOGY_COMPATIBLE,
+	"NO_BOH" = NO_BOH,
 ))
 
 DEFINE_BITFIELD(turf_flags, list(

code/datums/storage/subtypes/bag_of_holding.dm

@@ -16,6 +16,7 @@
 	return ..()
 
 /datum/storage/bag_of_holding/proc/recursive_insertion(obj/item/to_insert, mob/living/user)
+	var/area/bag_area = get_area(user)
 	var/safety = tgui_alert(user, "Doing this will have extremely dire consequences for the station and its crew. Be sure you know what you're doing.", "Put in [to_insert.name]?", list("Proceed", "Abort"))
 	if(safety != "Proceed" \
 		|| QDELETED(to_insert) \
@@ -24,6 +25,7 @@
 		|| QDELETED(user) \
 		|| !user.can_perform_action(parent, NEED_DEXTERITY) \
 		|| !can_insert(to_insert, user) \
+		|| (bag_area.area_flags & NO_BOH) \
 	)
 		return
 

code/modules/antagonists/heretic/knowledge/sacrifice_knowledge/sacrifice_map.dm

@@ -87,7 +87,7 @@ GLOBAL_LIST_EMPTY(heretic_sacrifice_landmarks)
 	has_gravity = STANDARD_GRAVITY
 	ambience_index = AMBIENCE_SPOOKY
 	sound_environment = SOUND_ENVIRONMENT_CAVE
-	area_flags = UNIQUE_AREA | NOTELEPORT | HIDDEN_AREA | BLOCK_SUICIDE
+	area_flags = UNIQUE_AREA | NOTELEPORT | HIDDEN_AREA | BLOCK_SUICIDE | NO_BOH
 
 /area/centcom/heretic_sacrifice/Initialize(mapload)
 	if(!ambientsounds)