Targeted fixes for the Arcanum Class Pack.

Arcanum Patches 1.2.0

This add-on focuses primarily on fixing Arcanum's enchantment and disenchantment
systems, including the severe slowdown and save growth caused by enchanting
multiple items, and permanent invincibility caused by broken Chaos Armour code.

Fixes

• Fixed escalating enchantment lag and save growth. Enchanted items were
  retaining full deep copies of themselves, the character, and the entire damn
  character's inventory. After only a handful of enchantments this could cause
  enormous savefiles, slow saving, severe lag, and eventual save failures and
  out-of-memory crashes.

• Added migration support for affected characters. Legacy enchanted items are
  detected on load and converted only after confirmation. Leftover references that
  kept discarded character copies alive are also cleaned up.

• Reworked Disenchant Item to reverse enchantments in place instead of
  restoring another deep item copy. This is now, oh... about 99.8% more efficient :D

• Fixed several Disenchant Item problems:
  • The self-target item picker now opens correctly.
  • Targeting no longer fails away from the map's x=y diagonal.
  • The level-4 "scrub all properties" option now produces the mundane base item.
  • Enchanted Pommel Gem no longer crashes after the clone-removal fix.
  • Ordinary gems recovered from enchanted items can stack normally again.

• Fixed Disenchant Creature targeting which was failing whenever a target
  wasn't on a simple x=y diagonal.

• Rune Strike now works with bows and slings, including proper ranged
  targeting and rune/gem flares on arrow hits.

• Fixed two Chaos Armour problems:
  • Aegis no longer leaves behind a permanent damage-negation value after Chaos
    Armour expires. At very high levels CA can still render an enemy invulnerable
    (100% reduction), but only until it wears off.
  • Chaos Armour expiry no longer throws a Lua error during its cleanup.

Existing characters

Back up your save before its first load with v1.2.0.

Existing saves maintain their own addon list. If the character has already used
Arcanum Patches, it should already be listed. If you are adding the addon to an
older character for the first time:

1. Enable Arcanum Patches normally.
2. Close the game.
3. Open that character's desc.lua under the T-Engine 4.0/tome/save/CHARACTER/ directory.
4. Add 'arcanum-patches' to its addons = {...} list.
5. Load the character and accept the migration prompt.

Enabling an addon globally only affects new characters - the above steps are needed to add arcanum-patches to an existing save.

Legacy items later retrieved from the floor, containers, or the official Items Vault are converted automatically.

More fixes *may* be added here later.