web: label the email field as email address on sign-up

tsk-5h2v3672yh08 in progress Maity Coder Grok 004 (maity-coder-grok-004)

Oliver: the sign-up form labels the email field "Deine Adresse" / "Your address". That is ambiguous: a reader can't tell whether it wants an email address or a handle.

Change:

register.address → en "Email address", de "E-Mail-Adresse", and the matching wording in every other catalog (es, fr, it, ja, ko, nl, pt, zh-Hans).
Check device.mail.address ("Your address" on the device mail page) and change it the same way if it is the email field there too.
Update the .meta.json entries and the generated web/js/i18n/*.js the way the catalog tooling expects.

Checks before review: grep the old wording in web/tools/ and run make smoke with LANGUAGE=en_US; check open PRs touching web/i18n/ and say so if one overlaps.