Add hover on i18n translations

[domingo2000]

First implementation for I18n support (#639)

How it works

1. Attach file watcher for all translation files
2. Add server request to reload translations on file changes. The reload is fast because does not need to reload the entire rails server, just the I18n.
3. Add server request to get I18n translations for all locales available in the I18n backend.
4. On hover of I18n.t("hello") key string argument, request the server all the translations available and provide hover info for that.

It address points 1 and 2 of the issue list:

1. Read what the translation says. e.g., I18n.t("hello") returns en: "Hello World", es: "¡Hola Mundo!".
2. Find out if a translation is missing.

And is usefull for updating and creating translations because it gives feedback that the used translations "is correct" because makes direct calls to the I18n backend while typing and hovering it. Warning if the translation is missing.

This gives the following experience:
Screencast from 2025-07-27 00-40-33.webm

[domingo2000]

This is provided because other I18n backend maybe does not implement the reloading feature.

[brunoprietog]

This could also be just t if we consider that you could be inside Action View, but perhaps that is beyond the scope.

[domingo2000]

Yes, its out of scope. This changes only support I18n.t("some-key") calls. With absolute key and string literal as argument.

To support t notation for ActionView, we need the context of which file is beign parsed and be able to complete the call of I18n in an ActionView context, or with the scope of that specific file. It could be a nice follow up if you want to help 👍🏻 .

[janko]

Would we need anything else other than the template filename to resolve a relative translation? I understand that you want to start with the simplest use case, I was just curious if we'd actually need the Action View context.