Add abnt-citation to Made in Brazil collection

[danielnichiata96]

Please confirm this pull request meets the following requirements:

• I followed the contributing guidelines: https://github.com/github/explore/blob/main/CONTRIBUTING.md.
• This change is not self-promotion.

Which change are you proposing?

• Suggesting edits to an existing topic or collection
• Curating a new topic or collection
• Something that does not neatly fit into the binary options above

---

Editing an existing topic or collection

I'm suggesting these edits to an existing topic or collection:

• Image (and my file is *.png, square, dimensions 288x288, size <= 75 kB)
• Content (and my changes are in index.md)

Why this project belongs in the Made in Brazil collection:

abnt-citation is a standalone open-source library (MIT license, zero dependencies) that provides a programmatic implementation of Brazilian ABNT citation standards — specifically NBR 6023:2025 and NBR 10520:2023.

This library solves a uniquely Brazilian problem: ABNT citation formatting has no other open-source programmatic implementation. Every Brazilian university student and researcher needs ABNT-formatted references, yet until now there was no reusable library to automate this.

Key highlights:

• Built in Brazil, for Brazil: Implements the official ABNT/NBR standards that are mandatory across all Brazilian academic institutions
• Portuguese/Brazilian name parsing: Handles compound surnames, particles ("da", "de", "do", "dos"), and other patterns specific to Brazilian and Portuguese names — functionality that is broadly useful beyond just citations
• Production-quality: 680+ tests, full TypeScript support, published on npm
• Broadly useful: Any Brazilian academic tool, writing assistant, or reference manager can use this library — it is a general-purpose building block, not tied to any specific product

This feels like a natural fit alongside other Brazilian community projects in this collection like BrasilAPI/BrasilAPI, bacen/pix-api, and okfn-brasil/querido-diario — open-source tools that address specifically Brazilian needs.