Simplify some Lorentz code

Description

Problem: once I added KnownValue constraint to sopGet because sometimes we need to call none within sopGet and such constraint is required there.

But in fact it is not convenient to have such constraints in primitives like get because one will have to propagate them everywhere in his code. It is better to have this constraint in methods composing Store*Ops because they are usually applied to concrete types and there is no need to propagate constraints.

Solution: remove KnownValue in sopGet, propagate changes.

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