Fix DPI scaling with TGUI, TGUI Say, and Tooltips (#20734)

Got tired of the issues here when working on something else.

Ported several PRs from /tg/station to fix DPI scaling issues. This was
not a problem before 516, however 516 now respects Window's DPI setting,
causing misalignment in several of our UI elements.

This PR implements these ~~four~~ ~~five~~ six PRs:
https://github.com/tgstation/tgstation/pull/65686
https://github.com/tgstation/tgstation/pull/89994
https://github.com/tgstation/tgstation/pull/90416
https://github.com/tgstation/tgstation/pull/90418
https://github.com/tgstation/tgstation/pull/90796
https://github.com/cmss13-devs/cmss13/pull/8734

~~Does not include fixes with TGUI-Say. /tg/station refactored TGUI-Say
after their port to React before they fixed DPI scaling, and this would
be pain to deconstruct to port over to Inferno. Since porting to React
is "inevitable", I considered it not worth my time to fix this.~~

Thanks to the assistance of harry, TGUI-Say fixes now included.

code/modules/tgui_input/say_modal/modal.dm

@@ -10,9 +10,7 @@
  * string - A JSON encoded message to open the modal.
  */
 /client/proc/tgui_say_create_open_command(channel)
-	var/message = TGUI_CREATE_MESSAGE("open", list(
-		channel = channel,
-	))
+	var/message = TGUI_CREATE_OPEN_MESSAGE(channel)
 	return "\".output tgui_say.browser:update [message]\""
 
 /**
@@ -36,6 +34,7 @@
 /datum/tgui_say/New(client/client, id)
 	src.client = client
 	window = new(client, id)
+	winset(client, "tgui_say", "size=1,1;is-visible=0;")
 	window.subscribe(src, PROC_REF(on_message))
 	window.is_browser = TRUE
 
@@ -62,11 +61,15 @@
  */
 /datum/tgui_say/proc/load()
 	window_open = FALSE
-	winshow(client, "tgui_say", FALSE)
+
+	winset(client, "tgui_say", "pos=700,500;is-visible=0;")
+
 	window.send_message("props", list(
-		lightMode = FALSE,
-		maxLength = max_length,
+		"lightMode" = client?.prefs.tgui_say_light_mode,
+		"scale" = client?.prefs.ui_scale,
+		"maxLength" = max_length,
 	))
+
 	stop_thinking()
 	return TRUE