[lua] Implement ELEMENTAL_DEBUFF_EFFECT

[wccbuck]

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• I have tested my code and the things my code has changed since the last commit in the PR and will test after any later commits.

What does this pull request do?

Implements the ELEMENTAL_DEBUFF_EFFECT item mod on items such as the Archmage's Sabots +3 and Agwu's Slops. This mod adds additional potency to spells such as Burn and Frost.

This PR also reorganizes some item mods from the "not implemented" section to their associated job section in the enum files.

Steps to test these changes

!changejob BLM 99
!additem 23780 (Agwu's Slops, elemental debuff effect +5)

Cast the spell Burn on a mob, and observe the amount of stat reduction and DoT (place a print in scripts/effects/burn.lua, inside onEffectGain). Once it wears off, equip the Agwu's Slops and cast Burn again. You should see the DoT go up by 5, and the stat reduction go up by 10. The item also has a sizable bonus to INT, so you may bump up to the next dINT tier and see +1 potency than you'd normally expect (+1 DoT and +2 stat reduction).