feat(i18n): complete Portuguese (Brazil) translation for UI and app

[RicSchonfelder]

Issue for this PR

Closes #35831

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

This PR completes the Portuguese (Brazil) translation for OpenCode by adding all missing keys in both:

• \packages/ui/src/i18n/br.ts\ (added 23 missing UI strings)
• \packages/app/src/i18n/br.ts\ (added 142 missing app strings)

All keys are now in full parity with the English source files. The translations cover:

• Session review UI, diff viewer controls, line comments
• WSL onboarding flow, home screen sessions
• Project/workspace management
• Settings UI (shell, file tree, navigation, terminal, status, mobile layout)
• Error pages and various missing keys throughout

How did you verify your code works?

• All keys match the English source (0 missing, 0 extra)
• Proper variable interpolation preserved ({{variable}})
• Tested language switching in the OpenCode desktop app

Screenshots / recordings

N/A - Translation-only change, no visual differences.

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR