The Compose form's "Send to" radio group had "All active users" checked
by default with no confirmation before Send -- anyone opening the
Dashboard to see how the feature works, typing a test subject/message,
and clicking Send would broadcast to every active user. Remove the
default (a target must now be explicitly chosen) and require a confirm
step before actually sending to "all" or "all_active".
Also add a hard safety net in models/email.js: Mail.send is a no-op
under NODE_ENV=test, so the automated test suite (which exercises the
real notification/password-reset/invite/OTP-by-email routes with
NODE_ENV=test) can never deliver real mail regardless of what recipient
list a test resolves.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>