Add contact status management and localization

[andreialecu]

• Introduced new status management for contacts, allowing updates to their subscription status (active, unsubscribed, unreachable).
• Updated the contact creation and update functions to handle status changes based on provided options.
• Enhanced test coverage for contact status updates during creation and modification.
• Added German, French, and English translations for the new status-related strings in the localization files.

Fixes #433

Recording:

CleanShot.2025-06-17.at.15.32.05.mp4

[andreialecu]

I'm not an Elixir user; it's my first time working with it, so I hope the changes are correct. Everything seems to work fine.

[andreialecu]

In this commit, bulk imports are also fixed so that the status column is taken into account and replaces the contact's existing status.

e4db4a1 (#437)

[wmnnd]

Hey there, like I wrote you in my email the other day, I appreciate your work on this PR but please break it down into two separate PRs for 1) changing the status on the edit page and 2) supporting the status import from CSV imports.
The second bit changes is significantly larger amount of code, so I'll have to review it separately.

[andreialecu]

Hey @wmnnd - unfortunately, my time is a bit short these days, but the changes are part of two individual commits.

Perhaps you can check them individually?

It would be great if you could take over and push your commits directly here, or do whatever you please with them.

Things seem to be running perfectly for my use, and are covered by tests.