Handle JATS assets (#9)

* Handle JATS assets

* Fix test

* Fix for real (and test)

* Better name

* Refactor

* Use S3

* Fix expression language usage and dev dependencies

* Fix PHPStan

* Remove duplication

* Set metadata

* Remove duplication

* Set region and fix errors

* Whitelist origin paths instead

* Easier to use a stream wrapper

* Tests

* Media type

* Test various assets, and fix attribute name

* Test origin check

* Not needed

* Avoid container config leaking into tests

* No longer needed

* Not needed either

* Use envvar

* Not meant/needed

* Use library

* Use bundle

* No longer needed

* Remove redundant variable and set in the test instead

* Match names elsewhere

* Better name

* Try and make a bit clearer

* Tweak

* Simplify and add basic test

* Require setting the public URI instead

* Refactor

* Use helper

* Add concurrency

* Ignore options

* Refactor, and introduce coroutine

* Avoid usi...