Abstract away ContainerRuntime and revisit IContainerRuntime

[vladsud]

IContainerRuntime represents "container level" API to some layers in the system (like request handler).
There is a lot of functionality provided by this interface, yet usage is tiny and some things are not used.
One of the reasons for that - we expose ContainerRuntime - particular implementation of that inteface.
The ideal workflow is for ContainerRuntime.load() to

1. return IContainerRuntime, not ContainerRuntime
2. Abstract it away behind factory function, such that there is little knowledge of that implementation outside ContainerRuntime / DataStoreContext layers.

That will allow us to better understand all the functionality that needs to be on that interface (might need to add), as well as functionality that we can remove from it.

[ghost]

This issue has been automatically marked as stale because it has had no activity for 180 days. It will be closed if no further activity occurs within 8 days of this comment. Thank you for your contributions to Fluid Framework!

[ghost]

This issue has been automatically marked as stale because it has had no activity for 180 days. It will be closed if no further activity occurs within 8 days of this comment. Thank you for your contributions to Fluid Framework!