docs(i18n): reorganize documentation by audience and add PT-BR corpus

[web2solutions]

Summary

• reorganize Jumentix docs by audience (consumers vs creators)
• keep internal planning/migration/governance docs out of consumer-facing website content
• add PT-BR documentation corpus across software docs (excluding .agents and .github)
• add and update tooling scripts for PT-BR documentation generation and link handling
• update website content source mapping to consumer-focused docs only

Governance

• requirement 076 updated to enforce no PT-BR mirroring for .agents/.github
• technical docs hub split by audience and linked from root README

Validation

• pre-commit hooks passed (changelog update, lint, unit tests)
• unit tests: 86/86 suites passed locally