End-to-end proof-of-life. bindAllDevSeed wires InMemoryEventBus +
InMemoryJobQueue across all features. signUpController publishes
auth.user.signed-up; marketing-pages' handler enqueues
marketing-pages.send-welcome-email; the in-memory queue dispatches
the wrapped job which records on RecordingMailerService.
Adds ./di/container, ./di/symbols, ./services/mailer, and
./services/recording-mailer to auth + marketing-pages exports so
the e2e test can resolve from the per-feature containers without
deep-importing.
Danijel Martinek
04899de98c