Implement bulk mail sending to admin panel

package-lock.json

package.json

src/lib/server/mail.ts

src/lib/server/notifications/emailHandler.ts

src/routes/admin/+page.svelte

src/routes/admin/api/users.ts

src/routes/admin/mail/+page.server.ts

src/routes/admin/mail/+page.svelte

src/routes/admin/mail/formatter.ts