* feat: add german, japanese, and chinese translations
adds complete translations for:
- german (de)
- japanese (ja)
- chinese simplified (zh)
builds on the internationalization foundation added in #437.
updates CONTRIBUTING_TRANSLATIONS.md to reflect supported languages.
* fix: escape Chinese quotation marks in zh translation
* cleanup
* remove extra keys for now
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Co-authored-by: CJ Pais <cj@cjpais.com>