When admin/customer emails were configured as optional in Settings >
Event Creation, the backend still rejected empty values because:
1. express-validator .optional() only skips undefined, not empty strings
— changed to .optional({ values: 'falsy' }) so "" is treated as
absent
2. DB columns host_email and admin_email had NOT NULL constraints
— added migration to make them nullable
3. Email queue insert crashed on null recipient_email
— skip queuing when no customer email is provided
Paul Nothaft
9c44a0ebfa