赵月辉 / fastgpt-migrated

* fix(i18n): optimize English translations for product-appropriate language

- Add 51 missing translation keys across 9 files
- Rewrite 69 literal/unnatural translations to product language
- Remove 3 orphaned keys not in source
- Ensure all 22 locale files pass structural validation
- Key improvements:
  - FAQ section: clearer, more concise answers
  - Dataset: 'Block' → 'Chunk', natural phrasing
  - App: better error messages and descriptions
  - Common: consistent terminology throughout

* Update packages/web/i18n/en/dataset.json

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

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Co-authored-by: OpenClaw Bot <bot@openclaw.ai>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>