feat: New Changed Aspect Ratio Event & Player::AspectRatio Property

[MS-crew]

Description

Describe the changes
Added ChangedRatio event to detect when a player's aspect ratio changes.

What is the current behavior? (You can also link to an open issue here)
Currently, Exiled has no way to detect or handle player aspect ratio changed.

What is the new behavior? (if this is a feature change)
New event triggers when player's aspect ratio changes, provides both old and new ratio values.

Does this PR introduce a breaking change? (What changes might users need to make in their application due to this PR?)
❌ No , This is purely additive functionality

Other information:

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