# About the pull request

Fixes/tweaks a couple of auto-observe things that I noticed after #5751.
Specifically:
- Fixes `runtime error: client_screen_add overridden. Use override =
TRUE to suppress this warning`/`runtime error: client_screen_remove
overridden. Use override = TRUE to suppress this warning`.
*This error was consistently thrown when a ghost who's body is being
observed re-enters their body. `observe_target_new_mind()` tries to
re-register the some signals on the body's new client, but didn't have
the `override` argument set.*

- Stops 'hidden' actions being added to the screen of observing players.
(e.g. the xeno tacmap action if the queen isn't ovied)

- Makes any observers transfer over to the new body when a xenomorph
evolves/de-evolves.
*(I also added `/mob/dead/observer` to the `observers` variable's
declaration since it wasn't particularly clear what the list held.)*

- Fixes the target player's action buttons disappearing for observers if
they reconnect or re-enter their body.
*(The actions were being shown to the player in
`Login()`>`show_hud()`>`update_action_buttons()` before the observer
could re-register signals in `observe_target_login()`.)
In order to fix this I renamed the existing `COMSIG_GLOB_MOB_LOGIN`,
`COMSIG_CLIENT_MOB_LOGIN`, `COMSIG_MOB_LOGIN` signals, and made
`COMSIG_MOB_LOGIN` send a bit earlier in the proc.*

# Explain why it's good for the game

Bugfixes :)


# Testing Photographs and Procedure
<details>
<summary>Screenshots & Videos</summary>

Put screenshots and videos here with an empty line between the
screenshots and the `<details>` tags.

</details>


# Changelog
:cl:
fix: Fixed 'hidden' action buttons being shown to observing players.
qol: Made any observers transfer over when a Xenomorph
evolves/de-evolves.
/:cl: