The password change form on the profile page (``Mes coordonnées``)
was scaffolded but never wired to any backend logic. The fields
``current-password``, ``new-password`` and ``new-password_confirmation``
were silently ignored by ``Customers::storeFull()``.
- Add ``handlePasswordChange()`` in ``CustomerController`` that
validates current password, confirmation match, and 8-char minimum
before hashing and saving.
- Remove ``required`` attribute from password fields so the form can
submit for profile-only updates without filling password fields.
- Strip password fields from request data before passing to
``storeFull()`` to avoid Eloquent mass-assignment noise.