Fix custom name mismatch at client disconnect

[Rainyan]

Description

WIP

In order to fix this, we gotta cache the last known valid player name, because:

neo/src/game/client/clientmode_shared.cpp

Lines 1137 to 1142 in 23343df

	// Josh: There used to be code here that would get the player entity here to get the name
	// Big problem with that. The player entity is probably already gone -- they disconnected after all!
	// So there used to be a bug where most of the time, disconnect messages just wouldn't show up in chat.
	//
	// The player's name who disconnected is already provided in the event, so there was no reason for all
	// of this logic anyway...

And because the player_disconnect event originates from the engine library, we gotta manually fix-up the player name after the fact.

Toolchain

• Windows MSVC VS2022

Linked Issues

• fixes When having fake nicknames on, the disconnect message can still show the steam name #445