Stops CTF players delivering the flag to the flag (#76789)

## About The Pull Request

Adds more warnings telling CTF players the flag has to be taken to the
controller to capture it by:

Text when picking up the flag
Text and angry buzz when trying to hit another flag with it

## Why It's Good For The Game

Players continue to obliviously drop flags on the ground on top of their
own flag despite being told what to do when joining the match, so this
information needs to be reiterated during the match when relevant to the
player.

## Changelog
🆑
qol: CTF has more reminders of how to capture flags.
/🆑

---------

Co-authored-by: san7890 <the@san7890.com>

code/modules/capture_the_flag/ctf_game.dm

@@ -256,9 +256,19 @@
 		anchored = TRUE // Avoid directly assigning to anchored and prefer to use set_anchored() on normal circumstances.
 		return
 	//passing means the user picked up the flag so we can now apply this
+	to_chat(user, span_userdanger("Take \the [initial(name)] to your team's controller!"))
 	user.set_anchored(TRUE)
 	user.status_flags &= ~CANPUSH
 
+/obj/item/ctf_flag/attackby(obj/item/item, mob/user, params)
+	if(!istype(item, /obj/item/ctf_flag))
+		return ..()
+		
+	var/obj/item/ctf_flag/flag = item
+	if(flag.team != team)
+		to_chat(user, span_userdanger("Take \the [initial(flag.name)] to your team's controller!"))
+		user.playsound_local(get_turf(user), 'sound/machines/buzz-sigh.ogg', 100, vary = FALSE, use_reverb = FALSE)
+
 /obj/item/ctf_flag/dropped(mob/user)
 	..()
 	user.anchored = FALSE // Hacky usage that bypasses set_anchored()