Start of initiative interruptions behave too much like genuine turn starts

[TacGit1]

Initiative interruptions are special, occurring when it isn't the unit's turn. In X2TacticalGameRuleset, in the function: SetupUnitActionsForGroupTurnBegin, it calls SetupActionsForBeginTurn from XComGameState_Unit. In SetupActionsForBeginTurn, things like untouchable, bGotFreeFireAction, and, very critically, CleanupUnitValues(eCleanup_BeginTurn) is here. This means if a skirmisher interrupts a turn, but had untouchable, a hair trigger occurrence, or had some eCleanup_BeginTurn unit values on them, they all get cleared as if their real turn has started.

As another example, if a templar had Interrupt and Parry, their Parry gets cleared on interruption.

I have a fix set up that uses unit values, though this will be my first submission to the CHL, so gonna need some help/time doing this properly.

[Iridar]

The key problem highlighted by this issue is that initiative interrupts tick unit values, but do not tick effects. This inconsistency means that interrupting initiative is kinda like a real turn from the standpoint of unit values, but not a real turn from the standpoint of effects.

Description of Interrupt and Battlelord also have no indication that initiative interrupts are meant to be "real turns", and instead just say "take an action".

As such, I believe unit values ticking during interrupts is a bug. Due to the deeply-rooted nature of initiative interrupts that go through Tactical Ruleset, I believe fixing this bug in Highlander would be appropriate, though in theory doing so might be breaking for existing mods that work tightly with interrupt mechanics.

This would not only be a bugfix, but also an alteration of base game mechanics, so in this case I would be comfortable with gating a fix for this bug behind a config toggle, and disabled by default.