[DOCS] Add Table of Contents to NPC Meta

[LordZibblington]

Documentation Issue Type

• Typo or grammatical error
• Incorrect or outdated information
• Unclear explanation or confusing content
• Missing documentation for a topic
• Broken links or images
• Code example not working
• Other (Document is difficult for mod developers to use)

Location

Page/File: /docs/official-documentation/npc-doc

Suggested Improvement

If you have suggestions for how to improve or fix the content:

Implement a table of contents