Adds true observing -- letting you see what your target sees (#24855)

* bring it back now y'all

* adds a bunch of other changes

* pretty much works at this point

* grep

* Fixes some bugs, still chasing some down

* Add observers to recursive mob check, ensuring they can see messages from their orbitted atom

* tidy some things up

* resolve

* remove unnecessary checks

* Address todos, minor cleanups

* oh dear

* initial testing

* Fix some vulnerabilities (oops)

* Fix some other bugs from testing

* ci fixes

* Add some contingencies against clicking things you shouldn't

* fix some noted bugs

* Add observe to admin jump, improve messaging

* add a few more fixes that should mostly address some runtimes

* oh this wasn't really great

* one last thing

* Fix suit inventory problem

* Remove merge artifact

* Add some missing parens

* Prevents you from observing other ghosts, and should fix the getting stuck outside of your body issue.

* we love testing

* adds to player panel

* Fix more bugs with observers getting stuck outside of their body

* cleans up player panel, verb offerings

* shit

* Update code/_onclick/hud/alert.dm

welp

Co-authored-by: GDN <96800819+GDNgit@users.noreply.github.com>
Signed-off-by: Luc <89928798+lewcc@users.noreply.github.com>

* Fixes some targeting issues

* Fixes targeting on aobserve

* Fix some weird storage bugs

* clean up some doulbed up follow links

* Update code/modules/admin/player_panel.dm

Signed-off-by: Luc <89928798+lewcc@users.noreply.github.com>

* Adds some checks for ghost observe

* Remove mentor debug log

* ahhhhhhhhh that'll do it

* Cleans up some additional checks that were not quite what they should have been

* better logging, too

* mochi review

* one more thing

* Gets robot huds mostly working

* hopefully fix folks not getting observe

* Fix order of operations causing a runtime on qdeleting

* Remove some unnecessary stack traces

* Apply suggestions from code review

Co-authored-by: 1080pCat <96908085+1080pCat@users.noreply.github.com>
Signed-off-by: Luc <89928798+lewcc@users.noreply.github.com>

* Fix bug with items in your inventory disappearing on changing HUD modes

* Fix some bugs with the observe verbs

* possibly fix nullspace issues

* funny review

* missed one

---------

Signed-off-by: Luc <89928798+lewcc@users.noreply.github.com>
Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: GDN <96800819+GDNgit@users.noreply.github.com>
Co-authored-by: S34N <12197162+S34NW@users.noreply.github.com>
Co-authored-by: 1080pCat <96908085+1080pCat@users.noreply.github.com>

code/modules/mob/mob.dm

@@ -27,6 +27,10 @@
 		viewing_alternate_appearances = null
 	LAssailant = null
 	runechat_msg_location = null
+	if(length(observers))
+		for(var/mob/dead/observe as anything in observers)
+			observe.reset_perspective(null)
+
 	return ..()
 
 /mob/Initialize(mapload)
@@ -600,7 +604,7 @@ GLOBAL_LIST_INIT(slot_equipment_priority, list( \
 	if(.)
 		// Allows sharing HUDs with ghosts
 		if(hud_used)
-			client.screen = list()
+			client.clear_screen()
 			hud_used.show_hud(hud_used.hud_version)
 
 //mob verbs are faster than object verbs. See http://www.byond.com/forum/?post=1326139&page=2#comment8198716 for why this isn't atom/verb/examine()