This patch removes the `with_service` helper from the code base.
Instead, we can pass a block with actions directly to the `.call` method
of a service.
This simplifies how to use services:
- use `.call` without a block to run the service and get its result
object.
- use `.call` with a block of actions to run the service and execute
arbitrary code depending on the service outcome.
It also means a service is now “self-contained” and can be used anywhere
without having to include a helper or whatever.
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