Values that fail validation are being stored as translation candidates (when not excluding validation group)

[NaLogo]

Hello!

When the validation group is not excluded from laravel-translation-manager, user input that fails validation will be added to the ltm_translations table. That input may contain confidential or otherwise privacy-related data like passwords, email addresses, etc.

While excluding the validation group is a valid workaround, it does come with its own downsides in terms of usability, as it will no longer be possible to edit or add to the standard validation group via the Translation Manager frontend.

Since I am not sure what an acceptable solution would look like (I would've otherwise developed something and opened a PR), I'm raising this issue and asking for input.

Unfortunately, the values are not namespaced, so - would skipping missingKey() in Manager.php for keys with the format "validation.values.*" be acceptable?
This could be tied to an additional config setting, if desired.

If you don't consider this an issue at all and you would not accept any PRs for this anyway, then I'll accept that, too.