An email-signup account's users.phone is a random, meaningless "888"
placeholder (see internal/domain/emailphone.go, cmd/createuser) -- the
account's own My Account / Edit Profile screen should show the email it
was actually created with instead, matching what an official client
displays there.
Only tgSelfUser substitutes signup_email for the phone; tgUser (how other
viewers see this account) is untouched, since the phone field there is
already privacy-gated and substituting the email would leak it past that
gate to anyone allowed to see a phone.
