core: Add / Improve French translation

[PingoLeon]

Thanks for maintaining this project, I tweaked and added some translations that were uncorrect / missing.
Please note it may not be perfect, feel free to improve it.

Note : re-did the pull request so that there's no more than one commit for these small changes.

[Myzel394]

Please note it may not be perfect, feel free to improve it.

Are you a native speaker of the French language?

Note : re-did the pull request so that there's no more than one commit for these small changes.

Okay no problem but it would also not be a problem to have more than one commit. More commits are actually better in most of the cases as they provide more granular control.

[PingoLeon]

Are you a native speaker of the French language?

Yes I am. I said that because in French there's many ways to say the same things but with whole different words (e.g : "Paramètres supplémentaires" = "Réglages Additionnels") and one translation may be slightly more accurate than others depending on the context.

More commits are actually better in most of the cases as they provide more granular control.

That's true but in my case, it was some lines missed after a push, and a single commit for just a few typos seemed a bit excessive to me.

[PingoLeon]

My bad, missed those in the second commit, should be good now.

[PingoLeon]

Didn't know that deleting my copy of the repo would close this PR, because I thought it had been merged.
Could you change the file with the content of https://github.com/Myzel394/NumberHub/pull/45/files (split view) please ?
Or should I re-open a PR ?

[Myzel394]

Please re-open it, this way you'll be authored correctly. Sorry, I wanted to merge after the ci:cd became green but forgot it