docs: clearer documentation on item events

[JayXTQ]

Description

Describe the changes
@Mikihero and I were discussing what all 3 of the item events do (Using, Used and UsingComplete) and it was confusing what did what, so Miki did some testing and this PR is to include all items that trigger what event and clearer documentation of what each event does exactly, as it currently looks like Used and UsingComplete are the same thing.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentations

Submission checklist

• I have checked the project can be compiled
• I have tested my changes and it worked as expected

Patches (if there are any changes related to Harmony patches)

• I have checked no IL patching errors in the console

Other

• Still requires more testing

[JayXTQ]

fyi the CI failed on getting references, so not my fault :3

[JayXTQ]

@Mikihero done

[MikeSus1]

💀🙏

[VALERA771]

OK if that's true

[JayXTQ]

@VALERA771 due to nobody else giving any negatives, you can probably merge this