7a7ef76c

By: Michael Lynch <git@mtlynch.io>

Return ErrUnregisteredEmail from NewSender instead of empty entry

NewSender now returns a magiclogin.ErrUnregisteredEmail error for
unknown addresses instead of silently returning an empty token entry.
Callers handle the error explicitly and redirect to /login/check-email.

Inline LoginConfirmPath into the dev creator and remove login_redirect.go.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
configuredevShellbackendbackend-devcheck-bashcheck-frontendcheck-go-formattingcheck-go-test-packagescheck-trailing-newlinecheck-trailing-whitespacediagramdocker-imagee2e-testsgo-testsimport-from-tinybeanslint-sqllittle-momentslittle-moments-devx86_64-linux