- Register IAmazonS3 as a singleton instead of scoped: the AWS SDK client is
thread-safe and manages its own connection pool, so one instance per DI scope
(per request / per job iteration) was wasteful and risked socket exhaustion
- AudioTranscoderService: start reading stdout/stderr before writing stdin to
remove the latent pipe-buffer deadlock shape
- Dispose the resized-picture MemoryStream in ResizePictureActivity
- Background jobs use PeriodicTimer instead of while + Task.Delay
Verified: Worker boots against RabbitMQ + Postgres in Docker with no captive-
dependency error (dev scope validation) and both jobs start.
Build: 0 warnings, 0 errors.