[WIP] Add initial Portuguese (pt) i18n setup (UI strings only)

[oliverigor27]

Adds initial Portuguese (pt) localization support

This PR introduces the initial Portuguese (pt) locale for the new Astro + Starlight documentation site.

The migration from Docusaurus to Astro/Starlight happened while this work was in progress, so the implementation was updated to follow the new internationalization structure.

🚧 Work in progress: this PR establishes the Portuguese locale and documentation structure. Content translation will be completed incrementally in follow-up contributions.

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Scope

Included:

• Added Portuguese (pt) locale to the Starlight configuration
• Added Portuguese documentation structure under src/content/docs/pt
• Added Portuguese landing page
• Enabled Portuguese language selection in the UI

Not included:

• Full documentation translation
• Review of all translated content
• Complete localization coverage

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Background

The project recently migrated from Docusaurus to Astro/Starlight.

This contribution adapts the original Portuguese localization work to the new architecture and establishes the foundation for future translation efforts.

The goal is to make Portuguese available as a supported locale while allowing documentation pages to be translated progressively over time.

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Changelog

1. Added pt locale configuration in astro.config.mjs
2. Added Portuguese documentation directory under src/content/docs/pt
3. Added Portuguese landing page (src/content/docs/pt/index.mdx)
4. Enabled Portuguese language selection in the documentation site

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Progress

• Setup pt locale
• Add Portuguese documentation structure
• Enable language selector integration
• Translate documentation content
• Review and complete missing translations

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Notes for reviewers

• This PR was updated after the migration from Docusaurus to Astro/Starlight.
• The focus is to establish Portuguese as a supported locale.
• Documentation translation will be completed progressively in future contributions.

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By contributing to this project, I agree to abide by the Code of Conduct:
https://github.com/feature-sliced/documentation/blob/main/CODE_OF_CONDUCT.md

[Solant]

hey 👋

recently we switched from docusaurus to the Astro framework with Starlight, so the content and translation workflow are a bit different: https://starlight.astro.build/guides/i18n/

[oliverigor27]

Thank you, @Solant

I'm going to update.

[oliverigor27]

Hi! 👋

I've updated this PR to follow the recent migration from Docusaurus to Astro/Starlight.

The original implementation was based on the previous i18n structure, so I rebased the work onto the new architecture and adapted it to the current localization workflow.

I was quite busy with my day job over the last few months and wasn't able to continue the contribution as planned. Now that I have some time available again, I'll resume the Portuguese translation effort starting this week.

At this stage, the goal is to establish Portuguese as a supported locale and provide the necessary documentation structure. I'll continue translating the content incrementally in follow-up contributions.

[Gaic4o]

Thanks so much! If there’s anything you need help with, please feel free to let me know.