Toggle the ability for the dead to vote in-game + understandability for the dead whether voting is disabled. (#84352)

## About The Pull Request

Adds a convenient switch to change the ability to vote dead (previously
only in the config), and also turns off the button and adds a tooltip to
let players know why they can't vote (previously, you could just click,
since the button wasn't turned off, but the vote didn't count).



https://github.com/tgstation/tgstation/assets/78199449/404aac9c-0b41-4c16-8ffd-2a435cf25e2c

## Why It's Good For The Game

At the right moments, you can just stop considering the opinions of dead
players.
The dead players will be able to understand why they can't vote.

## Changelog

🆑 Vishenka0704
qol: With voting turned off for the dead, you can now understand why you
can't vote (being dead).
admin: Voting switch for the dead players
/🆑

code/modules/admin/verbs/server.dm

@@ -74,6 +74,9 @@ ADMIN_VERB(toggle_ooc_dead, R_ADMIN, "Toggle Dead OOC", "Toggle the OOC channel
 	message_admins("[key_name_admin(user)] toggled Dead OOC.")
 	SSblackbox.record_feedback("nested tally", "admin_toggle", 1, list("Toggle Dead OOC", "[GLOB.dooc_allowed ? "Enabled" : "Disabled"]"))
 
+ADMIN_VERB(toggle_vote_dead, R_ADMIN, "Toggle Dead Vote", "Toggle the vote for dead players on or off.", ADMIN_CATEGORY_SERVER)
+	SSvote.toggle_dead_voting(user)
+
 ADMIN_VERB(start_now, R_SERVER, "Start Now", "Start the round RIGHT NOW.", ADMIN_CATEGORY_SERVER)
 	var/static/list/waiting_states = list(GAME_STATE_PREGAME, GAME_STATE_STARTUP)
 	if(!(SSticker.current_state in waiting_states))