fix: correct remove method signature and its calls

[kaaams]

Fix: GravePreSpawnEvent cancellation prevents item duplication Artillex-Studios/Issues#380

Description

Fixes a bug where cancelling a GravePreSpawnEvent would still create a grave with items inside while also dropping items on the ground, causing item duplication.

Problem

When GravePreSpawnEvent.setCancelled(true) was called:

• The grave was still created with items inside ❌
• Items were also dropped on the ground ❌
• This resulted in item duplication ❌

Solution

This PR implements proper event cancellation handling:

Changes Made

1. Modified remove() method signature in Grave.java:

   • Added boolean dropInventory parameter to control whether items should be dropped
   • Updated method logic to conditionally call removeInventory() based on the parameter

2. Fixed scheduler call in Grave.java:

   • Changed Scheduler.get().runAt(location, this::remove) to Scheduler.get().runAt(location, () -> remove(true))
   • This resolves the compilation error where method reference didn't match the new signature

3. Updated all remove() calls throughout the codebase:

   • AxGraves.java: grave.remove(true) - drops inventory on plugin disable
   • SpawnedGraves.java: oldest.remove(true) - drops inventory when limit exceeded
   • DeathListener.java: grave.remove(false) - prevents item drop when event is cancelled

4. Implemented proper cancellation handling in DeathListener.java:

   • When GravePreSpawnEvent is cancelled, the grave is removed without dropping items
   • This allows vanilla death behavior to handle item dropping naturally
   • Prevents the duplication issue completely

Expected Behavior After Fix

When GravePreSpawnEvent.setCancelled(true) is called:

• ✅ The grave is NOT created (removed immediately with remove(false))
• ✅ Items drop normally on the ground (vanilla behavior preserved)
• ✅ No duplication occurs

Testing

The fix ensures that:

• Normal grave creation still works as expected
• Event cancellation properly prevents grave creation
• Items are handled correctly in both scenarios

Breaking Changes

None. This is a bug fix that maintains backward compatibility while properly implementing the intended event cancellation behavior.

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Type: Bug Fix
Scope: Event handling and grave management
Impact: Prevents item duplication, fixes compilation errors