Adds Internet admin midi (#30457)

* Adds Internet admin midi

* Moves global regex into proc (shell_url_scrub)

* Moves shelleo to world
Adds quotes around the command in shelleo, to encapsulate it

* Admins can stop playing web sounds

* Revised internet midi extension order
Moved m4a to least preferred,
as it can potentially carry non-aac or non-mpeg-3 audio

* Kills \n in web sound

* play_web_sound availability based on config

* play web sound and shelleo tweaks

istypeless for in play web sound & readability parenthesis around binary AND
add return index defines for shelleo proc

* Security fix for play web sound

code/modules/client/preferences_toggles.dm

@@ -144,6 +144,9 @@ TOGGLE_CHECKBOX(/datum/verbs/menu/Settings/Sound, togglemidis)()
 	else
 		to_chat(usr, "You will no longer hear sounds uploaded by admins")
 		usr.stop_sound_channel(CHANNEL_ADMIN)
+		var/client/C = usr.client
+		if(C && C.chatOutput && !C.chatOutput.broken && C.chatOutput.loaded)
+			C.chatOutput.sendMusic(" ")
 	SSblackbox.add_details("preferences_verb","Toggle Hearing Midis|[usr.client.prefs.toggles & SOUND_MIDI]") //If you are copy-pasting this, ensure the 2nd parameter is unique to the new proc!
 /datum/verbs/menu/Settings/Sound/togglemidis/Get_checked(client/C)
 	return C.prefs.toggles & SOUND_MIDI