The onboarding Brand page was reusing settings.brand.* keys, which
coupled two unrelated pages: a rename in Settings would silently break
onboarding, and the two pages might want to diverge copy later (e.g.
more welcoming language during first-run vs terse settings labels).
Duplicated the relevant keys (field labels, placeholders, tone
options, content language copy) into onboarding.brand.* across
en/pt-BR/es. The Settings workspace page keeps using
settings.brand.* — they're the source of truth for that page now.
No behavior change; just separation of ownership.
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