[#728] Access MorleyClientEnv in network tests

Description

Problem: we sometimes need to access MorleyClientEnv in cleveland network tests. However, due to locking, we can't.

Solution: Introduce NetworkCaps that carries NetworkEnv and related instances/synonyms. Replace ScenarioCleveland with ScenarioNetwork. Reimplement scenario as a typeclass function lifting the corresponding ClevelandT into the appropriate monad. Add some convenience synonyms to avoid the typeclass constraint proliferation. Finally, instead of carrying Maybe EmulatedImpl in misc caps, carry Either EmulatedImpl NetworkEnv, so that ifEmulation can access NetworkEnv as well.

Related issue(s)

Resolves #728 (closed)

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