What does this PR do?

This PR introduces the initial Portuguese (Brazil) (pt-BR) translation for the Hyperf documentation, making the framework more accessible to Portuguese-speaking developers, especially in Brazil.

With Hyperf getting increasingly popular in Brazil, this helps lower the language barrier for a large and active developer community and supports continued adoption and community growth.

Scope of changes

• Added the base directory structure for the Portuguese (Brazil) translation (docs/pt-br/).
• Translated the core documentation pages (e.g., installation, configuration, core components).
• Translated the changelogs (docs/pt-br/changelog/), where applicable.
• Ensured all technical terms, code snippets, and PR links remain intact and accurate.
• Followed the established translation and formatting conventions used in the existing documentation.
• Used the English documentation as the base/reference for the translation.

Checklist

• I have read the Contributing Guide.
• I have translated the documents accurately while preserving technical terms.
• I have tested the markdown formatting locally to ensure there are no broken links or broken code blocks.
• I have maintained the same file structure as the English/Chinese documentation.