Clarify project setup methods

[galaxyofgamersofficial-stack]

Summary

• Clarify that there are two common ways to set up a Paper plugin project.
• Rename the existing section to "Manual project setup".
• Add links to both setup methods for easier navigation.

Testing

• Ran npx pnpm@latest run build successfully.
• Verified that all internal links are valid.

Closes #697

[github-actions]

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[Strokkur424]

This really does not have anything to do with the linked issue at all. I have a restructure of this page planned, so I will not be merging this PR. Thank you though.

[galaxyofgamersofficial-stack]

Thanks for letting me know! I understand. Since this was my first contribution, could you clarify what the linked issue was specifically expecting? I'd like to learn from this and make sure my future contributions address the intended problem.

[Strokkur424]

The current project setup page is fairly cluttered and does not flow well to a reader. The templates have been updated, so the mc-dev creation way is relevant again, but now is outdated. The latter part is not addressed in the issue but was talked about in #docs-website in the Discord server back when the issue was originally addressed.

Your change was not bad, it's just that I want to touch this page more in-depth, hence the close.