Fix disenchant skill check causing bots to pass on usable loot (#2478)

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## Pull Request Description
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When a bot has the Enchanting skill but its level is insufficient to
disenchant an item, the old code returned `ITEM_USAGE_NONE` immediately.
This caused the bot to pass on loot rolls for items it could have used
for other purposes (equip, quest turn-in, crafting reagents, guild
tasks) because the function never reached those downstream checks.

The fix combines the skill check and binding check into a single
positive condition: the bot only returns `ITEM_USAGE_DISENCHANT` when it
is both skilled enough and the binding allows it. Otherwise, execution
falls through to the remaining item usage evaluations as intended.

## Feature Evaluation
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- Describe the **minimum logic** required to achieve the intended
behavior.
- Describe the **processing cost** when this logic executes across many
bots.

- **Minimum logic:** Replace two separate guards (one early-return
`NONE`, one positive `DISENCHANT`) with a single combined `if` that
returns `DISENCHANT` only when both conditions are met. No new branches
— one fewer than before.
- **Processing cost:** Identical. The same two comparisons execute once
per disenchant-eligible item evaluation. No change to per-bot or
per-tick cost.

## How to Test the Changes
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1. Spawn a bot with Enchanting skill at a low level (e.g. 1/75).
2. Loot or roll on an armor/weapon item with `RequiredDisenchantSkill`
higher than the bot's skill (e.g. a level 50 blue with required skill
225).
3. **Before:** The bot returns `ITEM_USAGE_NONE` and passes on the item,
even if it could equip it or use it for a quest.
4. **After:** The bot correctly evaluates remaining usages (equip,
quest, etc.) and rolls Need/Greed appropriately.

## Impact Assessment
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tick) can help you here. -->
- Does this change increase per-bot/per-tick processing or risk scaling
poorly with thousands of bots?
    - - [x] No, not at all
    - - [ ] Minimal impact (**explain below**)
    - - [ ] Moderate impact (**explain below**)

Same number of comparisons, one fewer early-return path.

- Does this change modify default bot behavior?
    - - [ ] No
    - - [x] Yes (**explain why**)

Bots with insufficient enchanting skill will now correctly consider
non-disenchant uses for items they previously passed on entirely.

- Does this change add new decision branches or increase maintenance
complexity?
    - - [x] No
    - - [ ] Yes (**explain below**)

Reduces branches from two `if` statements to one.

## AI Assistance
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Was AI assistance used while working on this change?
- - [ ] No
- - [x] Yes (**explain below**)

AI was used to refactor the two-condition guard into a single combined
condition. The logic was reviewed and the behavioural difference
(fall-through vs early return) was verified manually.

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## Final Checklist

- - [x] Stability is not compromised.
- - [x] Performance impact is understood, tested, and acceptable.
- - [x] Added logic complexity is justified and explained.
- - [x] Any new bot dialogue lines are translated.
- - [x] Documentation updated if needed (Conf comments, WiKi commands).

## Notes for Reviewers
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The root cause was that `return ITEM_USAGE_NONE` on the skill check
short-circuited the entire `Calculate()` function, skipping all
downstream item usage evaluations. The fix simply lets execution
continue past the disenchant block when disenchanting isn't viable.

Co-authored-by: avirar <avirar@users.noreply.github.com>

src/Ai/Base/Value/ItemUsageValue.cpp

@@ -109,12 +109,9 @@ ItemUsage ItemUsageValue::Calculate()
         // Retrieve the bot's Enchanting skill level
         uint32 enchantingSkill = bot->GetSkillValue(SKILL_ENCHANTING);
 
-        // Check if the bot has a high enough skill to disenchant this item
-        if (proto->RequiredDisenchantSkill > 0 && enchantingSkill < proto->RequiredDisenchantSkill)
-            return ITEM_USAGE_NONE; // Not skilled enough to disenchant
-
-        // BoE (Bind on Equip) items should NOT be disenchanted unless they are already bound
-        if (proto->Bonding == BIND_WHEN_PICKED_UP || (proto->Bonding == BIND_WHEN_EQUIPPED && isSoulbound))
+        // Only disenchant if skilled enough and binding allows it
+        if (enchantingSkill >= proto->RequiredDisenchantSkill &&
+            (proto->Bonding == BIND_WHEN_PICKED_UP || (proto->Bonding == BIND_WHEN_EQUIPPED && isSoulbound)))
             return ITEM_USAGE_DISENCHANT;
     }