Minifies tgui helpers (#90340)

## About The Pull Request
Instead of just writing out the helper functions and styles directly
inside tgui.html, this minifies them and injects them into the document
on tgui init. The result should be a smaller bundle and more manageable
code, with clear separation of page, style, and javascript
## Why It's Good For The Game
Minification is generally a small perf gain but I want to be clear that
I'm doing this 100% for organization & separation of concerns
## Changelog
N/A

code/controllers/subsystem/tgui.dm

@@ -26,12 +26,24 @@ SUBSYSTEM_DEF(tgui)
 
 /datum/controller/subsystem/tgui/PreInit()
 	basehtml = file2text('tgui/public/tgui.html')
+
+	// Inject inline helper functions
+	var/helpers = file2text('tgui/public/helpers.min.js')
+	helpers = "<script type='text/javascript'>\n[helpers]\n</script>"
+	basehtml = replacetextEx(basehtml, "<!-- tgui:helpers -->", helpers)
+
+	// Inject inline ntos-error styles
+	var/ntos_error = file2text('tgui/public/ntos-error.min.css')
+	ntos_error = "<style type='text/css'>\n[ntos_error]\n</style>"
+	basehtml = replacetextEx(basehtml, "<!-- tgui:ntos-error -->", ntos_error)
+
 	// Inject inline polyfills
 	var/polyfill = file2text('tgui/public/tgui-polyfill.min.js')
-	polyfill = "<script>\n[polyfill]\n</script>"
+	polyfill = "<script type='text/javascript'>\n[polyfill]\n</script>"
 	basehtml = replacetextEx(basehtml, "<!-- tgui:inline-polyfill -->", polyfill)
 	basehtml = replacetextEx(basehtml, "<!-- tgui:nt-copyright -->", "Nanotrasen (c) 2525-[CURRENT_STATION_YEAR]")
 
+
 /datum/controller/subsystem/tgui/Shutdown()
 	close_all_uis()