Adds a new redgate map: The Casino Canal (#18587)

* starts da map

* starting to shape up I think?

* moar edits

* we got lots more stuff now

* we got dorms now :)

* moar doarm and PRIVATE GAME ROOMS WOAG

* adds chip machine

* tidy dis up

* oops

* pretties up private game rooms a bit

* ok now the chip dispenser works

* Adds resleeving stuff

* Adds pixel-displaced children of punlic paintings

* mmmmmm maint stuff

* adds VIP rooms and more maint stuff

* that's a lotta shit made woooo

* its almost... done... (the main building is anyway)

* Let's get this bih to actually load

* And let's get some proper areas separating indoor and outdoor

* Makes casino hall turfs actually render as intended

* WE HAVE AREAS NOW

* don't need this big ol file any more

* MOSTLY finishes the mai nbuilding

* finally finishes the main building (for now)

* does some exterior stuff but now it's crashing WHY

* oops

* adds subvariant of floodlight that starts turned on

* adds areas for well, secret areas

* TOO MUCH new shit

* Does a silly thing to make properly underwater cave turfs

* adds "open" underwater turfs that are functionally transparent divable turfs

* more funny secrets

* Makes open water turfs show a darker view underneath for visual clarity

* okay I think it might be done now

* makes indoor water effect look a bit nicer

* I ALMOST FORGOT

* engoodens code surrounding multiple auto-resleevers existing

* FUCK

* DOUBLE FUCK

* Lets things with GLASSPASS move through TGMC widnows

* actually it makes more sense for the TF gun to be here

* Makes 🏴‍☠️ secret a bit nicer

---------

Co-authored-by: Cameron Lennox <killer65311@gmail.com>

code/game/objects/structures/artstuff.dm

@@ -349,6 +349,18 @@
 	desc_with_canvas = "A piece of art (or \"art\"). Anyone could've hung it."
 	persistence_id = "public"
 
+/obj/structure/sign/painting/public/north
+	pixel_y = 30
+
+/obj/structure/sign/painting/public/south
+	pixel_y = -30
+
+/obj/structure/sign/painting/public/east
+	pixel_x = 30
+
+/obj/structure/sign/painting/public/west
+	pixel_x = -30
+
 /obj/structure/sign/painting/library_secure
 	name = "\improper Curated Painting Exhibit mounting"
 	desc = "For masterpieces hand-picked by the librarian."