Update the Node.js engine setting in service/package.json to use LTS v20
instead of the end-of-life v19. This aligns with our Dockerfile that
uses node:lts-alpine, which has been a while without issues. The update
also helps suppress the runtime warnings about engine compatibility:
> WARN Unsupported engine: wanted: {"node":"^16 || ^18 || ^19"} (current: {"node":"v20.12.2","pnpm":"9.0.4"})
* Additional English translations
Provide an English version of the readme, and add a few translations
that were missing elsewhere
* Use browser language by default
* Support 'en' and 'vi' as languages
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Co-authored-by: Ed Burnette <ed.burnette@hiddenmind.ai>