[Quest] Convert Scattered into Shadow to IF

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What does this pull request do?

Converts Beast AF2 Quest (Scattered into Shadow) to IF/Cleans up npc luas Implements Tehbi hiding TODO

Complete Beast AF2 Quest

There are 2 dialogs given by Brutus depending on whether or not you had previously declined the quest. So, first time -> long dialog, second time post decline -> short dialog.
The CS/event for each of the flora removals delivers the removal message
Tehbi disappears for 15 mins on successful beast collar trade
The Beast Collar is retrieved from a chest in CASTLE_OZTROJA thus we need to retrieve the quest var, Prog from outside the quest lua - there's a deprecated method in utils.lua (utils.getQuestVar) which effectively does the same as the code I've updated in treasure.lua for this quest. The deprecation comment says to use xi.quest methods but from my understanding you wouldn't be able to reach these methods without a quest so I've just left it implemented in place.
Previous PR: https://github.com/LandSandBoat/server/pull/6102