Improve localization

[EchoEllet]

Issue description

When I first created app_en.json and added the keys, I did it quickly. As a result, most keys lack clear descriptions, and while some keys are understandable in English, they may not translate the meaning clearly into other languages.

In particular, the key names should describe their purpose or context, not just the literal English text. This ensures that translations make sense in different languages and convey the intended meaning.

For example, in the case of an error, we might show Show details in English. However, the equivalent in another language could differ significantly, and simply translating the English text may not convey the intended meaning. Proper localization ensures a better user experience that feels natural and friendly to users in any language.

Additionally, the keys are not well organized or structured. We should consider refactoring the file thoroughly before adding more keys to maintain clarity and consistency.

// ❌ Bad (literal English text as key)
{
  "showDetails": "Show details"
}

// ✅ Good (descriptive key)
{
  "errorDialogShowDetailsButton": "Show details"
}

This report tracks this issue; although it does not provide more useful details on how we should solve the issue, it will be updated as the situation develops.

• Verify that numbers included in messages are properly localized and displayed correctly—for example, in authCodeServerStartFailurePortInUse.
• Avoid including technical details in user-facing messages. Example of a message that should be improved Add user-friendly option to view technical details for unclear errors (e.g., connection failures) #15 (comment)

Considerations

• Check out slang for localization support.
• A good example of a well-structured localization file: Zulip Flutter app