docs(pt-br): add getting started guide

[tompsantos]

Summary

Adds the Brazilian Portuguese translation of the Kimi Code CLI Getting Started guide and updates the localization project metadata.

Included

• docs/pt-br/guides/getting-started.md
• new onboarding terminology in PT-BR_GLOSSARY.md
• progress update in PT-BR_STATUS.md

Translation notes

• preserves commands, flags, paths, links, keyboard shortcuts, and literal UI labels
• translates natural-language prompt examples
• explains first-use jargon such as CLI, TUI, shell, and checksum
• tracks the known upstream wording inconsistency around standalone binary vs npm distribution instead of silently hiding it

Upstream context

The canonical English page currently documents both the standalone install script and npm installation, while an earlier introductory sentence still describes distribution only via npm/Node.js. The pt-BR page uses the behavior already documented by the installation section. The equivalent English clarification remains proposed in MoonshotAI#2664.

Validation

• source structure and section order preserved
• technical literals preserved
• relative links preserved
• VitePress containers checked
• code fence language tags preserved where required
• glossary updated for new recurring terms
• public progress tracker updated from 1/26 to 2/26 pages