Flags and adjacency work (#20259)

Added a bunch of flags for passflags on things that were previously
missing them.
Removed snowflake passthrow var, it's a passflag now.
Updated ClickCross and Adjacency code.
It's now possible to interact with things that are adjacent but
otherwise have a machine (or other appropriate items) blocking them, eg.
think of an APC on the wall with a machine in front of it.

code/modules/battlemonsters/items/furniture/dueling_area.dm

@@ -1,10 +1,10 @@
 /obj/structure/dueling_table
 	name = "dueling table"
 	icon = 'icons/obj/battle_monsters/furniture.dmi'
-	anchored = 1
-	density = 1
+	anchored = TRUE
+	density = TRUE
 	climbable = TRUE
-	throwpass = 1
+	pass_flags_self = PASSSTRUCTURE | LETPASSTHROW
 
 /obj/structure/dueling_table/no_collide
 	density = 0

code/modules/holodeck/HolodeckObjects.dm

@@ -331,9 +331,9 @@
 	desc = "Boom, Shakalaka!"
 	icon = 'icons/obj/basketball.dmi'
 	icon_state = "hoop"
-	anchored = 1
-	density = 1
-	throwpass = 1
+	anchored = TRUE
+	density = TRUE
+	pass_flags_self = PASSSTRUCTURE | LETPASSTHROW
 
 /obj/structure/holohoop/attackby(obj/item/attacking_item, mob/user)
 	if (istype(attacking_item, /obj/item/grab) && get_dist(src,user)<2)

code/modules/makeshift/makeshift_reagents.dm

@@ -3,10 +3,9 @@
 	icon = 'icons/obj/makeshift_workstation.dmi'
 	icon_state = "workstation"
 	desc = "It's a makeshift workstation for grinding, chopping, and heating."
-	density = 1
-
-	anchored = 1
-	throwpass = 1
+	density = TRUE
+	anchored = TRUE
+	pass_flags_self = PASSSTRUCTURE | LETPASSTHROW
 
 	var/obj/item/device/analyzer/analyzer
 	var/transfer_out = 0

code/modules/mob/mob_defines.dm

@@ -5,6 +5,7 @@
 	movable_flags = MOVABLE_FLAG_PROXMOVE
 	sight = DEFAULT_SIGHT
 	blocks_emissive = EMISSIVE_BLOCK_GENERIC
+	pass_flags_self = PASSMOB
 	var/datum/mind/mind
 	var/static/next_mob_id = 0
 

code/modules/tables/tables.dm

@@ -3,14 +3,13 @@
 	icon = 'icons/obj/structure/tables/table.dmi'
 	icon_state = "frame"
 	desc = "It's a table, for putting things on. Or standing on, if you really want to."
-	density = 1
-	anchored = 1
+	density = TRUE
+	anchored = TRUE
+	pass_flags_self = PASSTABLE | LETPASSTHROW
 	climbable = TRUE
 	layer = TABLE_LAYER
-	throwpass = 1
 	breakable = TRUE
 	build_amt = 1
-	pass_flags_self = PASSTABLE | LETPASSTHROW
 
 	//Preset shit
 	var/table_mat