Add Brazilian Portuguese (pt-BR) support

[roperes98]

📌 Pull Request: Add Brazilian Portuguese (pt-BR) support

✨ Summary

This PR adds full support for Brazilian Portuguese (pt-BR) to the library, including:

• Cardinal numbers (integers and decimals)
• Ordinal numbers
• Currency formatting (BRL - Real)

The implementation follows Brazilian Portuguese linguistic rules and CLDR conventions.

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🇧🇷 Features

🔢 Cardinal numbers

• Correct use of conjunction "e" between hundreds, tens, and units

  • Example: cento e vinte e três

• Proper handling of:

  • "cem" (exact 100)
  • "cento" (100+ remainder)

• Omission of "um" before "mil"

  • Example: mil (not um mil)

• Support for large numbers using short scale:

  • milhão (10⁶), bilhão (10⁹), trilhão (10¹²), etc.

🔟 Ordinal numbers

• Full ordinal support with proper composition:

  • primeiro, décimo segundo, centésimo, etc.

• Scalable to large numbers using ordinal scale forms:

  • milésimo, milionésimo, etc.

💰 Currency (BRL)

• Converts values to Brazilian Real format:

  • 1 → um real
  • 2.50 → dois reais e cinquenta centavos

• Handles pluralization correctly:

  • real / reais
  • centavo / centavos

• Optional "e" conjunction between reais and centavos

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⚙️ Implementation details

• Uses BigInt-based segmentation for efficient large number handling

• Modular structure aligned with existing parsers:

  • parseCardinalValue
  • parseOrdinalValue
  • parseCurrencyValue

• Optimized fast paths for:

  • < 1000
  • < 1,000,000

• Precomputed scale words (singular and plural)

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🧠 Language-specific rules covered

• Conjunction rules with "e"

• Irregular hundreds:

  • duzentos, trezentos, quinhentos, etc.

• Decimal separator: "vírgula"

• Negative numbers: "menos"

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✅ Examples

toCardinal(123)
// cento e vinte e três

toOrdinal(21)
// vigésimo primeiro

toCurrency(42.5)
// quarenta e dois reais e cinquenta centavos

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🚀 Notes

• Follows CLDR: pt-BR
• Designed to be consistent with existing language implementations
• No breaking changes

[TylerVigario]

Hey @roperes98, thanks for the pt-BR contribution — the implementation looks solid!

A couple of things are missing before we can merge:

1. Test fixture (test/fixtures/pt-BR.js) — needs cardinal, ordinal, and currency test case mappings filled out
2. LANGUAGES.md — needs regenerating (happens automatically with npm run lang:add)

I've got the scaffold ready on my end — I can push it to your branch if you'd like, or you can run npm run lang:add pt-BR yourself. Either way, just need you to fill in the test cases.

Let me know how you'd like to proceed!