Add Portuguese localization to projects folder

[vitorvasc]

• [x] I have read and followed the contribution guidelines, including the First-time contributing? note.
• [x] This PR includes AI generated content, and I have read and conform to the Generative AI Contribution Policy.

Adds the Portuguese localization efforts document to the projects folder. The document was created with assistance from Claude Opus 4.5, using references from existing content (blog posts, previous pull requests, etc.) and the current content in our 'Contributing' section.

/cc @open-telemetry/docs-pt-approvers