Linter Introduction + Cleanup (#8085)

* Adds linter defines to repo.

* Uncomments linter defines already in the code.

* Resolves unreachable code linter errors.

* Nukes decade+ old syndie specops code except for computer since that's mapped in?????

* Resolves procs has no parent linter error.

* Proc signature fixes

* Bad comments

* "In" danger

* Type safety

* Implied nested list abuse

* Top level ..() usage

* Sleepy coder typos

* Invalid kwargs calls

* Pointless returns

* Linter hacks (see full message)

Byond doesn't care and it has no effect but linter doesn't like var/proc
for holding references to procs, despite that it's valid byond code.

Also, the linter seems to have serious issues figuring out relative
proc names. This commit is a sort of take-it-or-leave-it thing. It's not
required, it just cuts down on warnings, but this code is valid DM code.

* WHATEVER THIS IS

* Trick dreamchecker linter into ignoring this file's sins in it's weird use of vars

* Fix list decoration syntax - Its a list, not list of lists

- To declare that a var is a list you can `var/list/blah = list()` syntax or the `var/blah[0]` syntax.  Both do exactly the same thing. But if you do `var/list/blah[0]` that is just like doing `var/list/list/blah = list()`

* Hopefully stops the ai holder subtype folder from going quantum and sometimes changes capitalization over time, and incidentally causing 20+ linter errors.

* Fixes unwrapped negated object in list linter error.

* Resolves colon-like list accessing linter error.

* Turns linter on in linter config.

* Fixes closet indentation properly and cleans up suit storage unit switch.

Co-authored-by: Aronai Sieyes <arokha@arokha.com>
Co-authored-by: Leshana <Leshana@users.noreply.github.com>

code/modules/maps/tg/map_template.dm

@@ -216,7 +216,7 @@
 			continue
 
 		// Did we already place down a very similar submap?
-		if(chosen_template.template_group && chosen_template.template_group in template_groups_used)
+		if(chosen_template.template_group && (chosen_template.template_group in template_groups_used))
 			priority_submaps -= chosen_template
 			potential_submaps -= chosen_template
 			continue

code/modules/maps/tg/reader.dm

@@ -139,7 +139,7 @@ var/global/use_preloader = FALSE
 			var/maxx = xcrdStart
 
 			// Assemble the grid of keys
-			var/list/key_list = list()
+			var/list/list/key_list = list()
 			for(var/line in gridLines)
 				var/list/line_keys = list()
 				xcrd = 1
@@ -165,7 +165,7 @@ var/global/use_preloader = FALSE
 			if(orientation != 0)
 				var/num_cols = key_list[1].len
 				var/num_rows = key_list.len
-				var/list/new_key_list = list()
+				var/list/list/new_key_list = list()
 				// If it's rotated 180 degrees, the dimensions are the same
 				if(orientation == 180)
 					new_key_list.len = num_rows