Hide stack visualization for fully-unexecuted evaluations

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While all evaluations occur during compilation, we can safely hide the internal stack visualization for evaluations which result in bytecode which is never executed. E.g. the stack visualization (current_block_time delay_seconds ...) for the evaluation in this locking script should be hidden since it's not relevant for the active unlocking script:

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Related: we should continue to show the stack visualization for internal evaluations even if their parent script is failing to compile. (Often, the internal evaluation being incorrect is the root cause of the outer compilation failure, but it's tedious to debug without a stack visualization for the internal evaluation.)

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Also related: there was a regression between 1846ad1 (deployed) and cd8c0a0 (deployed) in which spacers for lines ending inside internal evaluation are no longer nested within the spacers of the parent evaluation.

E.g. before:

After: