Canreach refactor (#93165)

## About The Pull Request
ports https://github.com/DaedalusDock/daedalusdock/pull/1144
ports https://github.com/DaedalusDock/daedalusdock/pull/1147

full credit to @Kapu1178 for the juice

instead of `reacher.CanReach(target)` we now do
`target.CanBeReachedBy(reacher)`, this allows us to give special
behavior to atoms which we want to reach, which is exactly what I need
for a feature I'm working on.
## Why It's Good For The Game
allows us to be more flexible with reachability
## Changelog
🆑
refactor: refactored how reaching items works, report any oddities with
being unable to reach something you should be able to!
/🆑

code/game/objects/structures/bedsheet_bin.dm

@@ -92,7 +92,7 @@ LINEN BINS
 	return ITEM_INTERACT_SUCCESS
 
 /obj/item/bedsheet/attack_self(mob/living/user)
-	if(!user.CanReach(src)) //No telekinetic grabbing.
+	if(!IsReachableBy(user)) //No telekinetic grabbing.
 		return
 	if(user.body_position != LYING_DOWN)
 		return

code/game/objects/structures/mystery_box.dm

@@ -174,13 +174,15 @@ GLOBAL_LIST_INIT(mystery_fishing, list(
 /obj/structure/mystery_box/proc/generate_valid_types()
 	valid_types = get_sane_item_types(selectable_base_type)
 
+/obj/structure/mystery_box/IsContainedAtomAccessible(atom/contained, atom/movable/user)
+	return TRUE
+
 /// The box has been activated, play the sound and spawn the prop item
 /obj/structure/mystery_box/proc/activate(mob/living/user)
 	box_state = MYSTERY_BOX_CHOOSING
 	update_icon_state()
 	presented_item = new(src)
 	presented_item.vis_flags = VIS_INHERIT_PLANE
-	presented_item.flags_1 |= IS_ONTOP_1
 	vis_contents += presented_item
 	presented_item.start_animation(src)
 	current_sound_channel = SSsounds.reserve_sound_channel(src)

code/game/objects/structures/tables_racks.dm

@@ -1145,7 +1145,7 @@
 	tool.play_tool_sound(src, 50)
 	balloon_alert(user, "mask detached")
 	UnregisterSignal(breath_mask, list(COMSIG_MOVABLE_MOVED, COMSIG_ITEM_DROPPED))
-	if (user.CanReach(breath_mask))
+	if (breath_mask.IsReachableBy(user))
 		user.put_in_hands(breath_mask)
 	breath_mask = null
 	update_appearance()
@@ -1160,7 +1160,7 @@
 	air_tank.forceMove(drop_location())
 	tool.play_tool_sound(src, 50)
 	balloon_alert(user, "tank detached")
-	if (user.CanReach(air_tank))
+	if (air_tank.IsReachableBy(user))
 		user.put_in_hands(air_tank)
 	if (patient?.external && patient.external == air_tank)
 		patient.close_externals()
@@ -1192,7 +1192,7 @@
 		. += span_notice("There's a port for a breathing mask tube on its side.")
 
 /obj/structure/table/optable/proc/detach_mask(mob/living/user)
-	if (!istype(user) || !user.CanReach(src) || !user.can_interact_with(src))
+	if (!istype(user) || !IsReachableBy(user) || !user.can_interact_with(src))
 		return FALSE
 
 	if (!breath_mask)
@@ -1208,7 +1208,7 @@
 	return TRUE
 
 /obj/structure/table/optable/mouse_drop_dragged(atom/over, mob/living/user, src_location, over_location, params)
-	if (over != patient || !istype(user) || !user.CanReach(src) || !user.can_interact_with(src))
+	if (over != patient || !istype(user) || !IsReachableBy(user) || !user.can_interact_with(src))
 		return
 
 	if (!air_tank)

code/game/objects/structures/water_structures/toilet.dm

@@ -165,7 +165,7 @@
 			grabbed_mob.adjustBruteLoss(5)
 		return
 
-	if(cistern_open && !cover_open && user.CanReach(src))
+	if(cistern_open && !cover_open && IsReachableBy(user))
 		if(!LAZYLEN(cistern_items))
 			to_chat(user, span_notice("The cistern is empty."))
 			return