Update to 1.21.2

[ChampionAsh5357]

Applies the contribution formatting and updates the docs to 1.21.2. This is a separate section due to the large number of changes between versions.

Waiting On

• [1.21.3] Expose RecipeManager#recipes NeoForge#1620
• Xfact's updates to IClientExtensions for armor model setup

Relevant Issues

Closes #177
Closes #179
Closes #180
Closes #181
Closes #183
Closes #196
Supersedes #174

Subsections

• Advanced
• Block Entities
• Blocks
• Concepts
• Data Storage
• Getting Started
• GUI
• Items
• Legacy
• Misc
• Networking
• Resources
  • Client
    • Models
  • Server
    • Data Maps
    • Enchantments
    • Loot Tables
    • Recipes
• World Generation

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[neoforged-pages-deployments]

Deploying with Cloudflare Pages

Name	Result
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PR Preview URL:	https://pr-178.neoforged-docs-previews.pages.dev

[XFactHD]

Looks good to me now. Just a couple comments from TG remaining unresolved.

[ChampionAsh5357]

I have resolved everything I plan to implement in this PR. Anything else I'm leaving out for a separate PR.

[IchHabeHunger54]

Two small things I noticed, should be good to go otherwise.