Mitigation for the exploding phantom tree bug

[SilasD]

this is closely based on ab9rf's work:
https://discord.com/channels/793331351645323264/807444515194798090/1537901782515318876
more discussion in DFHack Discord #feature-discuss
https://discord.com/channels/793331351645323264/807444515194798090/1537577051073290281
and in Kitfox Discord #bug-discussion
https://discord.com/channels/329272032778780672/1049402643342168114/1537342125543530507

verified that this runs ok.

accidentally pushed directly to the main scripts repo.
guess that's because I have privileges now.
glad I was in a new branch. guess I'll continue.

[chdoc]

This looks technically solid, I just had some comments on the documentation. You went a bit overboard on paragraphs. If a sentence uses references like "these" to expand on a previous sentence, I wouldn't put a paragraph break in between.

[chdoc]

There is no need for duplicating the documentation.

Suggested change

	-- removes "phantom" trees before they can explode.
	--[====[
	fix/exploding-trees
	===================
	By default, this script runs once a month by the Control Panel's Bug Fixes tab.
	This script mitigates a longstanding Dwarf Fortress bug.
	Once a year, trees check if they should grow. The exact day and time of this
	growth is different for every tree.
	Occasionally, when a tree is cut down or otherwise removed from the game, the
	game engine doesn't remove the tree's data from the list of plants. The exact
	details of this are not currently understood.
	For some reason, these "phantom" trees will sometimes collapse during this
	growth. This can stun, injure, or kill units which happen to be near this
	collapse.
	This script finds those trees and sets their dead flag, preventing them from
	growing and collapsing.
	--]====]

[chdoc]

please fix!

[chdoc]

Suggested change

	By default, this script runs once a month by the Control Panel's Bug Fixes tab.
	By default, this script is run once a month by the control panel. This can be disabled in the ``Bug Fixes`` tab.

[chdoc]

Suggested change

	This script mitigates a longstanding Dwarf Fortress bug.
	This script mitigates the "exploding trees" bug in Dwarf Fortress.

[chdoc]

Suggested change

	Once a year, trees check if they should grow. The exact day and time of this
	growth is different for every tree.
	Occasionally, when a tree is cut down or otherwise removed from the game, the
	game engine doesn't remove the tree's data from the list of plants. The exact
	details of this are not currently understood.
	Once a year, trees check if they should grow. The exact day and time of this
	growth is different for every tree. Occasionally, when a tree is cut down or
	otherwise removed from the game, the game engine doesn't remove the tree's
	data from the list of plants. The exact details of this are not currently understood.

[chdoc]

Suggested change

	For some reason, these "phantom" trees will sometimes collapse during this
	growth. This can stun, injure, or kill units which happen to be near this
	collapse.
	This script finds those trees and sets their dead flag, preventing them from
	growing and collapsing.
	These "phantom" trees will sometimes collapse during this growth. This
	can stun, injure, or kill units which happen to be near this collapse. This
	script finds those trees and sets their dead flag, preventing them from
	growing and collapsing.

[ab9rf]

Community feedback has determined that setting the vegst to DEAD is not enough to mitigate the bug; we have to actually delete the vegst in question. This is significantly harder to do. It may make more sense to fold this into the existing plants plugin, which (as I recall) already has some of the code needed for this.

[SilasD]

okay, converting this to draft.

I think I'll still finish out the requested changes, as practice. today or tomorrow.